\citep 问题在 overleaf 中

Question

我正在 overleaf 上写一篇论文。一切都很完美。然后我纠正了文本中的拼写错误（不是代码中的）。然后问题就开始了……所有的文内引用都变成了粗体，\citep不起作用，参考文献也都消失了。我正在使用编译器路拉泰克斯 不知道发生了什么...请帮忙这里是代码：

\documentclass[12pt,a4paper]{article}

\usepackage{enumerate}  
\usepackage{fancyhdr}
\usepackage[left=1.18in,
            right=1.57in,
            bottom=2.54cm]{geometry}
\usepackage{graphicx}
\usepackage{palatino}
\usepackage{multirow}
\usepackage{fontspec}
 \renewcommand{\baselinestretch}{1.5}
\setmainfont{Times New Roman}
\usepackage{booktabs}
\usepackage{titlesec}
\usepackage{acronym}
\usepackage{enumitem}
\usepackage[ngerman, english]{babel}
\usepackage[utf8]{inputenc}
\usepackage[bookmarks]{hyperref}
\usepackage[justification=centering]{caption}
\usepackage[style=authoryear,natbib=true,backend=biber]{biblatex}
\usepackage{csquotes}
\bibliography{ref}
\usepackage{lipsum}
\setlength{\parindent}{0em} 
\setlist[itemize]{noitemsep, topsep=0pt}
\setlist[enumerate]{noitemsep, topsep=0pt}

\emergencystretch=1em
\usepackage{ragged2e}
\justifying

\begin{document}

\begin{titlepage}
   
\end{titlepage}

  \clearpage
\newpage
\lhead{Abstract}
\section*{Abstract}

\thispagestyle{empty}
\newpage
\lhead{}
\pagenumbering{Roman} 
    \setcounter{page}{1}

\tableofcontents
\clearpage

\newpage
\section*{}
\addcontentsline{toc}{section}{List of Figures} 
\listoffigures

\newpage
\lhead{List of Tables} 
\addcontentsline{toc}{section}{List of Tables} 
\listoftables
\newpage

\setlength{\parskip}{0.5em} 

\lhead{List of abbreviations} 
\section*{List of abbreviations} 
\addcontentsline{toc}{section}{List of abbreviations} 

\begin{acronym}
 \acro{}
\end{acronym}

\clearpage
\pagenumbering{arabic}  
    \setcounter{page}{1}
\lhead{\nouppercase{\leftmark}}

\section{Introduction} \label{Introduction}

\subsection{section 2}
\lipsum[2]

\subsection{subsection}

\lipsum[2]
\subsubsection{sub-subsection}

\lipsum[2]

\section{citation \& references}
\lipsum[2]



\section{another section}


\clearpage
\newpage
\section{Reference}
\lhead{}
\printbibliography[type=article,title={Articles}]
\printbibliography[type=report,title={Reports}]
\addcontentsline{toc}{section}{\bibname}

\clearpage
\appendix
\section{Appendix A} 
\end{document}