大家晚上好。当我尝试运行下面这段代码时，我总是只能在序言中使用。请需要你的帮助。
\documentclass[12pt,A4,english]{report}
\usepackage{setspace}
\usepackage[english]{minitoc}
%\usepackage{geometry}
\usepackage[left=40mm,right=25mm, top=25mm, bottom=25mm]{geometry}
%\setlength{\oddsidemargin}{0.9cm}
%\setlength{\topmargin}{-0.94cm}
%\setlength {\evensidemargin }{-0.04 cm}
\usepackage{amsmath}
\usepackage{latexsym,verbatim}
\usepackage{amssymb}
\usepackage{amsfonts}
\usepackage{amsthm}
\usepackage{syntonly,indentfirst}
\usepackage{graphicx}
\usepackage{invoice}
%\usepackage{graphicx}
\usepackage[final]{pdfpages}
\usepackage{fancyhdr,txfonts}
%\textheight=22cm \textwidth=16cm
\frenchspacing %\linespread{2}
\usepackage{fancyhdr}
\usepackage{makeidx}
%\fancyhf{} % cancels header and foot pr\'ed\'efinis
%\fancyhead[L,R]{\bfseries\thepage}% Left Even, Right Odd
%\fancyhead[L]{} % Left Odd
%\fancyhead[R]{} % Right Even
%\renewcommand{\headrulewidth}{1.5pt}% filet en haut de page
%\addtolength{\headheight}{2.pt} % espace pour le filet
%\renewcommand{\footrulewidth}{0.5pt}% filet en bas de page
\renewcommand{\headrulewidth}{0pt} % et le filet
%\lhead{\textbf{\thepage}} %{\textsl{\rightmark}}
\fancypagestyle{plain}{
\fancyhf{} % clear all header and footer fields
\fancyhead[RO,RE]{\thepage} %RO=right odd, RE=right even
}
\pagestyle{myheadings}
% Don't bother to report over-full boxes if over-edge is < 2pt
% Line spacing -----------------------------------------------------------
\newlength{\defbaselineskip}
\setlength{\defbaselineskip}{\baselineskip}
\newcommand{\setlinespacing}[1]%
\frenchspacing\linespread{1.5}
\makeatletter
\newcommand{\thechapterwords}
{ \ifcase \thechapter\or ONE\or TWO\or THREE\or FOUR\or FIVE\or SIX\or SEVEN\or EIGHT\or NINE\or TEN\or ELEVEN\fi}
\def\@makechapterhead#1{%
%\vspace*{50\p@}%
%\vspace*{15\p@}%it is to increase the distance between the to and chapter number
{\parindent \z@ \centering \reset@font
\scshape \@chapapp{} \thechapterwords
\par\nobreak
\Huge \bfseries #1\par\nobreak
\par
\vspace*{15\p@}%
\vskip 2\p@
%\vskip 100\p@
}}
\def\@makeschapterhead#1{%
%\vspace*{50\p@}%
%\vspace*{15\p@}%it is to increase the distance between the to and chapter number
{\parindent \z@ \centering \reset@font
\par\nobreak
\Huge \bfseries #1\par\nobreak
\par
\vspace*{15\p@}%
\vskip 2\p@
%\vskip 100\p@
}}
\def\@makechapterhead#1{%
%\vspace*{50\p@}%
%\vspace*{15\p@}%it is to increase the distance between the to and chapter number
{\parindent \z@ \centering \reset@font
\scshape \@chapapp{} \thechapterwords
\par\nobreak
\Huge \bfseries #1\par\nobreak
\par
\vspace*{15\p@}%
\vskip 2\p@
%\vskip 100\p@
}}
\fancyhf{} % supprime les en-têtes et pieds prédéfinis
\fancyhead[L,R]{\bfseries\thepage}% Left Even, Right Odd
\fancyhead[L]{\bfseries\rightmark} % Left Odd
\fancyhead[R]{\bfseries\leftmark} % Right Even
\renewcommand{\headrulewidth}{0pt}% filet en haut de page
\addtolength{\headheight}{1pt} % espace pour le filet
%\renewcommand{\footrulewidth}{0.5pt}% filet en bas de page
%\addtolength{\footheight}{0.5pt} % espace pour le filet en bas
%\fancypagestyle{plain}{ % pages de tetes de chapitre
%\fancyhead{} % supprime l'entete
%\fancyfoot{} %supprime le pied de page
%\renewcommand{\headrulewidth}{0pt}
%}
\newcommand{\clearemptydoublepage}{%
\newpage{\pagestyle{plain}\cleardoublepage}}
%\lhead{\textsl{\leftmark}}
%\fancyfoot[RO]{\tiny \textbf{W.}}
%\fancyfoot[LO]{\tiny \textbf{MSc. Thesis In Mathematics }}
\rhead{\textbf{\thepage}}
%\lhead{\textsl{\leftmark}}
\newcommand{\I}{\textrm{$\mathrm{i}$}}
\newcommand{\U}{\textrm{$\mathcal{U}$}}
\newcommand{\N }{\textrm{$\mathbb{N}$}}
\newcommand{\Z }{\textrm{$\mathbb{Z}$}}
\newcommand{\R }{\textrm{$\mathbb{R}$}}
\newcommand{\Q }{\textrm{$\mathbb{Q}$}}
\newcommand{\C }{\textrm{$\mathbb{C}$}}
\newcommand{\vo }{\textrm{$\varOmega$}}
\newcommand{\B }{\textrm{$\mathbb{B}$}}
\newtheorem{thm}{\textbf{Theorem}}[section]
\newtheorem{lem}[thm]{\textbf{Lemma}}
\newtheorem{prop}[thm]{\textbf{Proposition}}
\newtheorem{claim}[thm]{\textbf{Claim}}
\newtheorem{result}[thm]{\textbf{Result}}
\newtheorem{rmk}[thm]{\textbf{Remark}}
\newtheorem{dfn}[thm]{\textbf{Definition}}
\newtheorem{expl}[thm]{\textbf{Example}}
\newtheorem{counter-expl}[thm]{\textbf{Counter-example}}
\newtheorem{cor}[thm]{\textbf{Corollary}}
\newtheorem{note}{\textbf{Note}}
\pagenumbering{roman}\addtocounter{page}{-1}
\begin{document}
\begin{center}
\textbf{UNIVERSITY OF BUEA}
\end{center}
\vspace{1cm}
\noindent \textbf{FACULTY OF SCIENCE \hspace{2.5cm} DEPARTMENT OF MATHEMATICS}
\vspace{2cm}
\begin{flushleft}
{\noindent\textbf{$L^{p}-L^{q}$ RATIONAL OF BERGMAN TYPE OPERATORS OVER THE SIEGEL UPPER HALF-SPACE }}
\end{flushleft}
\vspace{2cm}
\begin{center}
\textbf{By\\}
\end{center}
\vspace{1cm}
\begin{center}
\begin{singlespace}
\textbf{ Tallie Peka Ronald }\\
\small{B.Sc in Mathematics}
\end{singlespace}
\end{center}
\vspace{2cm}
\begin{center}
\begin{singlespace}
A Thesis Submitted to the Department of Mathematics, Faculty of
Science\\
of the University of Buea in Partial Fulfilment of
the Requirements\\ for the Award of the Master of Science (M.Sc.)\\ Degree in Mathematics
\end{singlespace} .
\end{center}
\vspace{2.6cm}
\begin{center}
September, 2020
\end{center}
\begin{center}
\textbf{UNIVERSITY OF BUEA}
\end{center}
\vspace{1cm}
\noindent \textbf{FACULTY OF SCIENCE \hspace{2.5cm} DEPARTMENT OF MATHEMATICS}
\vspace{2cm}
\begin{flushleft}
{\noindent\textbf{$L^{p}-L^{q}$ BOUNDEDNESS OF BERGMAN TYPE OPERATORS OVER THE SIEGEL UPPER HALF-SPACE }}
\end{flushleft}
\vspace{2cm}
\begin{center}
\textbf{By\\}
\end{center}
\vspace{1cm}
\begin{center}
\begin{singlespace}
\textbf{ Tallie Peka Ronald }\\
\small{B.Sc in Mathematics}
\end{singlespace}
\end{center}
\vspace{2cm}
\begin{center}
\begin{singlespace}
A Thesis Submitted to the Department of Mathematics, Faculty of
Science\\
of the University of Buea in Partial Fulfilment of
the Requirements\\ for the Award of the Master of Science (M.Sc.)\\ Degree in Mathematics
\end{singlespace} .
\end{center}
\vspace{2.6cm}
\end{document}