I can´t write under my table and 2 white pages appear

Question

I hope somebody can help me. I have problems with my code. Im starting with latex but im getting crazy. I created some tables but i have problems with them. I cant write under the last table, 2 new pages appear and the index is out of range for some reason.

Can someone lend me a hand? :) This is the whole code: %=================================================================

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\usepackage{multirow}
\usepackage{paracol}
%Título
\Title{Habits and risks in the use of social media
in Spanish teenagers: a delphi study}
%Autor documento
\Author{Firstname Lastname}
% Autor para PDF
\AuthorNames{Firstname Lastname}
% Abstract (Do not insert blank lines, i.e. \) 
\abstract{The habits of incorrect use of the social media by teenagers can have consequences for them
as victims, but also as offenders. The objective is to know the vision of experts on the use of
social networks by adolescents, of how their relationships are in social networks and what is
the knowledge of these by the parents, as well as the actions of adolescents in conflictive and
criminal situations. For this, a Delphi methodology has been used, in which 12 experts on
adolescent problems related to the misuse of social networks have been surveyed. After two
rounds, a high consensus was obtained in several dimensions of analysis (addiction, parental
control, risk perception and attitudes), obtaining as a conclusion that there is a lack of
knowledge on the part of adolescents of the consequences of an incorrect use of social media.
The findings reveal the need for a change in the training of adolescents, since although they
receive training on this subject in their educational centers, it follows that it does not manifest
itself in a variation in their way of acting when using social networks.}
% Keywords
\keyword{Social media, teenagers, cybercrime, addiction, training.}
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\begin{document}
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\section{Introduction}
\noindent This research aims to make an approach to the reality of the use that the child and teenagers
population makes of social networks; in which new technologies are combined with the way
of communicating and relating.\
\noindent In the first place, it is highlighted that social networks occupy a large part of the time that
adolescents spend on the Internet: 59% on average according to the study by \textcolor{blue}{[\underline{3}]} being 30% in
adolescents between 10 and 13 years old and reaching 82% in adolescents between 13 and 16
years old. In addition, 56% of adolescents have a profile on a social network according to  \textcolor{blue}{[\underline{8}]}.
The possibilities that social networks offer them as content generators and even the ability to
create an identity with which they are comfortable and be able to share information with
many people in their environment or outside of it, are some of the characteristics that they
have made the use of social networks is popular among adolescents, who have gone from
being content consumers to being content creators, especially multimedia \textcolor{blue}{[\underline{12}]}.\
\noindent Secondly, the relationships that occur in the RRSS are considered, on the one hand, it is
shown that the need for acceptance by others is also transferred to social networks. As \textcolor{blue}{[\underline{21}]}
points out, a kind of competition is created among adolescents to obtain the greatest possible
approval from the nucleus of virtual friends.\
\noindent The viral content that young people access mostly have elements that ridicule someone or are
violent in nature. Some of them encourage their repetition and are usually found on free
access platforms such as YouTube. For example, the phenomenon known as happy slapping
\textcolor{blue}{[\underline{23}]}, consisting of the recording of videos where a victim is added, humiliated and violent,
stands out to later upload and share them on the network.\
\noindent According to \textcolor{blue}{[\underline{24}]} to the adolescents surveyed, someone had done or said something to them
that they had disliked through the Internet being: 9.6% through WhatsApp, Messenger, etc.,
Social Networks 3.8 % and email 5.2%. This shows how abusive or harassing behaviors in
the physical world are extrapolated to the virtual world.\
\noindent Thirdly, in the face of this positive aspect of social networks, conflictive and criminal
situations in RRSS also stand out, with both short and long-term consequences, which
unfortunately are on the rise in this vital stage. Since, they are usually the medium in which
cyberbullying is practiced, being one of the people who threaten that individuals of this age
segment may suffer to denigrate their image and spread it in a way that is echoed among a
large public. Along the same lines \textcolor{blue}{[\underline{10}]}, it shows that approximately 8% of the adolescents
surveyed recognize themselves as cyberbullying or cyber-victims. Between these two groups
it is also observed that they make an increase in the use of ICT (Information and
Communication Technologies), which is greater in the case of cyberbullies, who also present
a greater dependence on these new technologies.\
\noindent Likewise, it is one of the most important sources for the collection of personal information
from adolescents, whether for marketing or purely malicious purposes, since, in them, these
subjects usually expose their entire lives. Specifically, video games are considered the
simplest way for adults to establish contact with adolescents, for inappropriate purposes, such
as grooming \textcolor{blue}{[\underline{15}]}. In turn, they cause a certain dependency, since they continually want to see
what their friends are and expose what they do to feed their virtual profile. It can be a
consequence of ignorance or unconsciousness related to their age, in which lack of maturity
becomes a factor that increases exposure to this type of risk behavior.\
\noindent Studies such as \textcolor{blue}{[\underline{12}]} deal with the perception of risk by adolescents, defining themselves as
“the ability to detect, identify and react to problematic situations when browsing the
internet”. On the existence of this knowledge there are numerous relevant investigations such
as \textcolor{blue}{[\underline{7}]}.\
\noindent Sexting is a voluntary practice, increasingly widespread among young people, which can lead
to child pornography content. There is a double typology: on the one hand, the images or
recordings can be made in a trusted environment, and they are directed only for one person;
and on the other hand, photographs of the adolescent with a markedly sexual pose, which is
shared through their social networks. In this case, it may be a crime of exhibitionism, which
responds to a low awareness of the existing risk, as well as an excess of confidence on the
part of the minor \textcolor{blue}{[\underline{19}]}.\
\noindent Prolonged exposure to digital content can have two immediate consequences: the first, access
to inappropriate or harmful content for the minor and its development \textcolor{blue}{[\underline{6}]}, and the second,
addiction to this type of content. The motivations that can lead to accessing inappropriate
content are abundant and tend to have a common denominator of curiosity and the need of
adolescents to assert themselves as independent adults, regardless of parental supervision.On the other hand, it is necessary to differentiate between access to harmful content, which is
legal but harmful for the proper personal and social development of adolescents; and access
to illegal topics, in which the protection of the minor can be done by legal means.\
\noindent This study is part of a wider investigation on the legal repercussions of the actions that
adolescents carry out in social networks. The objective is to know the vision of experts on the
use of social networks by adolescents, of how their relationships are in social networks and
what is the knowledge of these by the parents, as well as the actions of adolescents in
conflictive and criminal situations. \vspace{2cm}
\section{Materials and Methods}
\noindent This study was developed during the months of April to December 2019. The Delphi
methodology was used to carry out this study, in which surveys will be carried out to experts
in the domain of this research. The Delphi methodology falls within qualitative research
techniques. This technique is widely used in studies in Social Sciences as pointed out \textcolor{blue}{[\underline{20}]},
belonging to the group of expert methods, in which it is based on the opinions of
connoisseurs of the problem to be analyzed. A Delphi panel was carried out with two rounds,
and a third round was not considered necessary, as it would not provide a significant
improvement in the knowledge of the problem and it could lead to the abandonment of some
of the experts [\textcolor{blue}{[\underline{1}]}-\textcolor{blue}{[\underline{14}]}, p.102). The criteria of qualitative studies (COREQ) \textcolor{blue}{[\underline{25}]} have been
taken into account to report the study. Figure 1 shows the phases of the design used.
\begin{figure}[H]
\caption{\label{fig1} \ Design and execution phases of the Delphi methodology used in the study.\ }
\includegraphics[width=10.5 cm]{Definitions/Figura1.png}
\ \centering{Source: Own elaboration based on \textcolor{blue}{[\underline{9}]}.}
\end{figure}
\noindent Deliberate sampling is carried out, it is a non-probability sampling technique in which the
members of the sample are chosen only because of the researcher´s knowledge and judgment
\textcolor{blue}{[\underline{16}]}. It was decided in the first approach that 17 experts were an optimal number for the first
round, since it is between the 7 and 30 recommended in \textcolor{blue}{[\underline{14}]}, and considering possible losses,
14 answered the first questionnaire and 12 the second questionnaire, taking into account all
the responses obtained in each of the Delphi phases. In the first call, one person replied that
her profile was not related to the investigation and another was left without an answer, in the
second round both remained without response, and two did not continue.\vspace{0.5cm}
\noindent In the selection of the profiles of the experts (E), their training (researchers on adolescents,
addiction, RRSS, among others) and their profession (directors of secondary institutes, tutors
of public institutes and partners, social workers, psychologists, lawyers and police). Table 1
shows the list of anonymized experts, detailing the reason that prevailed for their selection:
(1) closeness to the investigated group; (2) research on the subject; (3) knowledge of the
subject and consequences.\vspace{2cm}
\begin{figure}[H]
\caption{\label{fig1} \ Design and execution phases of the Delphi methodology used in the study.\ }
\includegraphics[width=10.5 cm]{Definitions/Figura1.png}
\ \centering{Source: Own elaboration based on \textcolor{blue}{[\underline{9}]}.}
\end{figure}
\begin{quote}
\begin{center}
Source: Own elaboration.
\end{center}
\end{quote}
\subsection{Variables and Instruments}
To give the experts freedom to generate new ideas, in the first round, free-response questions
were posed \textcolor{blue}{[\underline{17}]} Table \ref{tab2}, which allowed obtaining more complete answers \textcolor{blue}{[\underline{2}]}. The analysis
of the responses allowed us to obtain a series of key concepts based on which the
questionnaire for the second round will be articulated. \
The second round was developed during the months of October to December 2019, with the
extraction, treatment and interpretation of the data taking place at the end of this. A closed
formulation questionnaire with an assessment scale was used, to collect the consensus
opinion. Possible responses to the second questionnaire consisted of assessing the degree of
conformity with a statement by selecting a number from 1 to 5 that it was identified with
being totally in disagreement (1) to totally agreeing (5) according to a Likert scale and using
the IBM SPSS Statistics software the standard deviation of each item was analyzed, obtaining
as a result the degree of consensus between the different experts. \
Following, Table \ref{tabla:fusionandoceldas} presents the list of topics, categorized by study dimensions (D):
D1. Addiction to Social Media (SM): habit of dangerous behaviors or excessive consumption
of time, which cannot be dispensed with or it is very difficult to do so for reasons of
psychological or behavioral dependency.
D2. Parental control: the knowledge of what the children do and the control they have over
them is revealed as a fundamental piece in this problem.
D3. Attitudinal: behavior that minors have on social networks and their relationship with
those they have in offline life.
D4. Risk perception: knowledge that minors have of the risks that their habits of use may
have on social networks, as well as the consequences thereof.
\begin{table}[htb]
\begin{tabular}{|l|l|}
\hline
\rowcolor[gray]{0.7}Dimension & Topic \
\hline 
\multirow{2}{3cm}{Addiction} & Too much time expensed in SM \ \cline{2-2}
& Disconnection with real life \ \hline
\multirow{4}{3cm}{Parental control}& Inefficient or incomplete parental control \ \cline{2-2}
& Treatment with the problems with parents\ \cline{2-2}
& Need of being always connected\ \cline{2-2} & 
Differences between online and offline life\ \hline
\multirow{3}{3cm}{Attitudinal} & Transcendence of offline life to online life \ \cline{2-2}
& Change in the paradigm of interpersonal
communication\ \cline{2-2}
& Need of appreciation in SM\ \hline
\multirow{10}{3cm}{Risk perception} & Sense of freedom \ \cline{2-2}
& Sense of impunity\ \cline{2-2}
& Sense of being anonymous\ \cline{2-2}
& Lack of knowledge of the concept of digital identity\ \cline{2-2}
& Ignorance of the consequences of their actions\ \cline{2-2}
& Ignorance of the nature of their actions\ \cline{2-2}
& Type of shared material\ \cline{2-2}
& Multiplying effect of SM\ \cline{2-2}
& Normalization of violent, sexist and racist content\ \cline{2-2}
& Ignorance of the risks related to SM\ \hline
\end{tabular}
\caption{Source: Own elaboration.}
\label{tabla:fusionandoceldas}
\end{table}
\subsection{Procedure and ethical aspects}
\end{document}```