here is my code
\documentclass[12pt,oneside]{report}
\usepackage[a4paper,tmargin=1in,bmargin=1in,rmargin=1in,lmargin=1in]{geometry}
\usepackage[american]{babel}
\usepackage{amsfonts,amssymb,amsmath,amsthm,mathtools}
\usepackage[table]{xcolor}
\usepackage{pifont}
\usepackage{marvosym}
\usepackage{fancybox,fancyhdr}
\usepackage{graphicx}
\usepackage{eso-pic}
\usepackage{booktabs,tabularx}
\usepackage{pdfsync}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[dvips]{epsfig}
\usepackage{caption,subcaption}
\usepackage{csquotes}
\usepackage[backend=biber,style=apa]{biblatex}
\usepackage{algorithmicx}
\usepackage[ruled]{algorithm}
\usepackage{algpseudocode}
\DeclarePairedDelimiter{\norm}{\lVert}{\rVert}
\captionsetup{labelfont=bf,skip=0.5\baselineskip,justification=raggedright,singlelinecheck=false}
\usepackage{hyperref}
\addbibresource{distbib.bib}
\begin{document}
\include{titlepage}
\pagenumbering{roman}
\include{Abstract}
\tableofcontents
\listoftables
\listoffigures
\eject
\pagenumbering{arabic}
\include{intro}
\include{chap23}
\printbibliography
\end{document}
apa6? – Mico Mar 27 '20 at 06:10apa6document class is thegeometrypackage. Since your professed goal is to apply APA style to the entire document, the obvious solution is to stop loading thegeometrypackage in the preamble. Incidentally, the optionlabelfont=bfin the\captionsetupinstruction would appear to be in conflict with the prescribed look of theapa6document class (which requires non-bold italics). – Mico Mar 27 '20 at 07:15\include{files}instruction in your code. (Aside: My divination skills are sadly non-existent.) – Mico Mar 27 '20 at 07:48figureandtableenvironments in the subfiles is creating a problem under theapa6document class? – Mico Mar 27 '20 at 08:03\chapterinstruction -- theapa6andapa7document classes do not provide a definition of\chapter. You will need to manually change all\chaptercommands to\section, all\sectioncommands to\subsection, etc. – Mico Mar 27 '20 at 09:18