LyX: Bibliography problem when previewing a PDF

Question

First of all, I'm sorry for my English (I am Spanish). I am writing my thesis with LyX and managing my references with Zotero. My document class is Book (Standard Class) and the style format is Biblatex. I was following these steps that were working for me:

1. From Zotero, export my bibliography to Biblatex (UTF) in a .bib file
2. Import the bibliography in LyX with Insert / List / Bib(la)TeX
3. Insert citation
4. Preview the PFD with [PDF(pdflatex]

But yesterday it stopped working out of the blue and I haven't touched anything! Now, when I preview the PDF it doesn't show the bibliography index nor the in-text citations (only the Cite key in bold). This is my document preamble:

    #LyX 2.3 created this file. For more info see http://www.lyx.org/
\lyxformat 544
\begin_document
\begin_header
\save_transient_properties true
\origin unavailable
\textclass book
\use_default_options true
\maintain_unincluded_children false
\language spanish
\language_package auto
\inputencoding auto
\fontencoding global
\font_roman "default" "default"
\font_sans "default" "default"
\font_typewriter "default" "default"
\font_math "auto" "auto"
\font_default_family default
\use_non_tex_fonts false
\font_sc false
\font_osf false
\font_sf_scale 100 100
\font_tt_scale 100 100
\use_microtype false
\use_dash_ligatures true
\graphics default
\default_output_format default
\output_sync 0
\bibtex_command default
\index_command default
\paperfontsize 12
\spacing onehalf
\use_hyperref false
\papersize default
\use_geometry false
\use_package amsmath 1
\use_package amssymb 1
\use_package cancel 1
\use_package esint 1
\use_package mathdots 1
\use_package mathtools 1
\use_package mhchem 1
\use_package stackrel 1
\use_package stmaryrd 1
\use_package undertilde 1
\cite_engine biblatex
\cite_engine_type authoryear
\biblio_style plain
\biblatex_bibstyle authoryear
\biblatex_citestyle authoryear
\use_bibtopic false
\use_indices false
\paperorientation portrait
\suppress_date false
\justification true
\use_refstyle 1
\use_minted 0
\index Index
\shortcut idx
\color #008000
\end_index
\secnumdepth 3
\tocdepth 3
\paragraph_separation indent
\paragraph_indentation default
\is_math_indent 0
\math_numbering_side default
\quotes_style french
\dynamic_quotes 0
\papercolumns 1
\papersides 1
\paperpagestyle default
\tracking_changes false
\output_changes false
\html_math_output 0
\html_css_as_file 0
\html_be_strict false
\end_header

I am a bit desperate, please help! Thank you, dear Internet.

Update: I am adding the LaTeX log (Biber):

[0] Config.pm:311> INFO - This is Biber 2.16
[0] Config.pm:314> INFO - Logfile is 'Tesis.blg'
[83] biber-darwin:340> INFO - === Sat Oct 23, 2021, 13:57:34
[99] Biber.pm:415> INFO - Reading 'Tesis.bcf'
[211] Biber.pm:952> INFO - Found 52 citekeys in bib section 0
[240] Biber.pm:4340> INFO - Processing section 0
[250] Biber.pm:4531> INFO - Looking for bibtex format file '0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib' for section 0
[255] bibtex.pm:1689> INFO - LaTeX decoding ...
[348] bibtex.pm:1494> INFO - Found BibTeX data source '0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib'
[390] Utils.pm:395> WARN - Entry 'hernandez_redondo_diego_2000' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2000' of date field 'date' - ignoring
[394] Utils.pm:395> WARN - Entry 'menendez_gonzalez_traza_2019' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2019' of date field 'date' - ignoring
[397] Utils.pm:395> WARN - Entry 'gomez-moreno_diego_1988' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1988' of date field 'date' - ignoring
[399] Utils.pm:395> WARN - Entry 'villacampa_capilla_1928' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1928' of date field 'date' - ignoring
[402] Utils.pm:395> WARN - Entry 'marias_franco_largo_1989' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1989' of date field 'date' - ignoring
[405] Utils.pm:395> WARN - Entry 'aceto_cappella_2010' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2010' of date field 'date' - ignoring
[408] Utils.pm:395> WARN - Entry 'gaeta_tra_2016' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2016' of date field 'date' - ignoring
[411] Utils.pm:395> WARN - Entry 'naldi_magnificence_2018' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2018' of date field 'date' - ignoring
[413] Utils.pm:395> WARN - Entry 'gomez-moreno_aguilas_1983' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1983' of date field 'date' - ignoring
[416] Utils.pm:395> WARN - Entry 'rotili_arte_1976' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1976' of date field 'date' - ignoring
[420] Utils.pm:395> WARN - Entry 'strazzullo_edilizia_1968' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1968' of date field 'date' - ignoring
[422] Utils.pm:395> WARN - Entry 'leone_de_castris_roma_2015' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2015' of date field 'date' - ignoring
[425] Utils.pm:395> WARN - Entry 'belloso_martin_barrio_2006' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2006' of date field 'date' - ignoring
[426] Utils.pm:395> WARN - Entry 'acerbo_guida_2008' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2008' of date field 'date' - ignoring
[433] Utils.pm:395> WARN - Entry 'migliaccio_consecratio_1994' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1994' of date field 'date' - ignoring
[436] Utils.pm:395> WARN - Entry 'tafuri_sobre_1995' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1995' of date field 'date' - ignoring
[439] Utils.pm:395> WARN - Entry 'di_resta_sullattivita_1992' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1992' of date field 'date' - ignoring
[442] Utils.pm:395> WARN - Entry 'lotz_representacion_1984' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1984' of date field 'date' - ignoring
[444] Utils.pm:395> WARN - Entry 'migliaccio_tomba_2017' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2017' of date field 'date' - ignoring
[449] Utils.pm:395> WARN - Entry 'merino_gomez_representacion_2015' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2015' of date field 'date' - ignoring
[449] Utils.pm:395> WARN - Entry 'merino_gomez_representacion_2015' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2021-09-27' of date field 'urldate' - ignoring
[452] Utils.pm:395> WARN - Entry 'ferraro_napoli_2002' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2002' of date field 'date' - ignoring
[455] Utils.pm:395> WARN - Entry 'bologna_problemi_1950' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1950' of date field 'date' - ignoring
[457] Utils.pm:395> WARN - Entry 'speranza_sul_2003' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2003' of date field 'date' - ignoring
[460] Utils.pm:395> WARN - Entry 'norman_succorpo_1986' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1986' of date field 'date' - ignoring
[461] Utils.pm:395> WARN - Entry 'norman_succorpo_1986' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2021-09-27' of date field 'urldate' - ignoring
[463] Utils.pm:395> WARN - Entry 'godby_note_1980' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1980' of date field 'date' - ignoring
[466] Utils.pm:395> WARN - Entry 'dominguez_parela_perspectiva_1991' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1991' of date field 'date' - ignoring
[469] Utils.pm:395> WARN - Entry 'toajas_roger_artistas_2007' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2007' of date field 'date' - ignoring
[472] Utils.pm:395> WARN - Entry 'panofsky_perspectiva_1983' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1983' of date field 'date' - ignoring
[476] Utils.pm:395> WARN - Entry 'ampliato_use_2020' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2020' of date field 'date' - ignoring
[478] Utils.pm:395> WARN - Entry 'bologna_aggiunta_1988' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1988' of date field 'date' - ignoring
[481] Utils.pm:395> WARN - Entry 'zurla_domenico_2013' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2013' of date field 'date' - ignoring
[484] Utils.pm:395> WARN - Entry 'madurell_marimon_bartolome_1948' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1948' of date field 'date' - ignoring
[487] Utils.pm:395> WARN - Entry 'gutierrez_martinez_estudio_1973' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1973' of date field 'date' - ignoring
[490] Utils.pm:395> WARN - Entry 'sanchez_diana_burgos_1969' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1969' of date field 'date' - ignoring
[492] Utils.pm:395> WARN - Entry 'carande_thovar_carlos_1977' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1977' of date field 'date' - ignoring
[495] Utils.pm:395> WARN - Entry 'lleo_canal_nueva_1993' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1993' of date field 'date' - ignoring
[498] Utils.pm:395> WARN - Entry 'polanco_melero_tensiones_2001' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2001' of date field 'date' - ignoring
[501] Utils.pm:395> WARN - Entry 'lovett_espanprimeros_1986' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1986' of date field 'date' - ignoring
[512] Utils.pm:395> WARN - Entry 'zalama_rodriguez_diego_1992' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1992' of date field 'date' - ignoring
[515] Utils.pm:395> WARN - Entry 'ampliato_idea_1991' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1991' of date field 'date' - ignoring
[519] Utils.pm:395> WARN - Entry 'speranza_escalera_2001' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2001' of date field 'date' - ignoring
[520] Utils.pm:395> WARN - Entry 'speranza_escalera_2001' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2021-10-04' of date field 'urldate' - ignoring
[523] Utils.pm:395> WARN - Entry 'huidobro_serna_artistas_1922' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1922' of date field 'date' - ignoring
[527] Utils.pm:395> WARN - Entry 'ruiz_de_la_rosa_control_1986' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1986' of date field 'date' - ignoring
[530] Utils.pm:395> WARN - Entry 'marias_franco_problema_1979' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1979' of date field 'date' - ignoring
[533] Utils.pm:395> WARN - Entry 'ampliato_muro_1996' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1996' of date field 'date' - ignoring
[537] Utils.pm:395> WARN - Entry 'redondo_cantera_luci_2013' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2013' of date field 'date' - ignoring
[540] Utils.pm:395> WARN - Entry 'ainaud_contrato_1948' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1948' of date field 'date' - ignoring
[546] Utils.pm:395> WARN - Entry 'martinez_monterio_genesis_2014' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2014' of date field 'date' - ignoring
[549] Utils.pm:395> WARN - Entry 'marias_franco_sobre_1990' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '1990' of date field 'date' - ignoring
[552] Utils.pm:395> WARN - Entry 'comune_di_napoli_progetto_2014' (0_Users_eacosta_Library_Mobile_Documents_com_ap___022_Doctorado_Texto_Cap__tulo_2_CAPITULO_II.bib): Invalid format '2014' of date field 'date' - ignoring
[554] Utils.pm:395> WARN - I didn't find a database entry for 'touring_club_italiano_napoli_1931' (section 0)

Also, in the LaTeX log (LaTeX) I found this warning:

Package biblatex Warning: 'babel/polyglossia' detected but 'csquotes' missing.
(biblatex)                Loading 'csquotes' recommended.

And this other for every citation:

LaTeX Warning: Citation 'hernandez_redondo_diego_2000' on page 1 undefined on i
nput line 26.
Underfull \hbox (badness 10000) in paragraph at lines 26--26
[][]\T1/cmr/m/n/10 Para una dis-cu-si�n so-bre la fe-cha de su na-ci-mien-to, v
er
 []

Uptade 2: I am adding some screenshots. The first one is the settings for the bibliography:

The second one, is the problem that I have. Now the citations don't show as expected, instead they appear with the Cite key: