我在 latex 文档中使用 \cormark[1] 时出错

Question

这是我的代码：

\documentclass[a4paper,fleqn]{cas-dc}
\usepackage[authoryear,longnamesfirst]{natbib}
\def\tsc#1{\csdef{#1}{\textsc{\lowercase{#1}}\xspace}}
\tsc{WGM}
\tsc{QE}
\usepackage{authblk}

\begin{document}
\let\WriteBookmarks\relax
\def\floatpagepagefraction{1}
\def\textpagefraction{.001}
\shorttitle{Tackling the bottlenecks of ...}    
\shortauthors{Reza et~al.}  
\title [mode = title]{Tackling the bottlenecks of videos}  
\author[1]{Morteza}[role=senior advisor,
            orcid=0000-0000-0000-0000]
\cormark[1]
\fnmark[1]
\ead{[email protected]}
\ead[url]{www.example.com}
\credit{Conceptualization of this study, Methodology, Softwar}
\affiliation[1]{organization={University of example},
            addressline={V94 T9PX}, 
            city={example},
%       citysep={}, % Uncomment if no comma needed between city and postcode
%         postcode={}, 
            state={},
            country={Ireland}}

以及文档的其余部分。每当我运行此代码时，都会收到以下错误：

...to_str:N \csgdef {mark@corau\theau@ }{1}} l.86 \cormark[1]

？

我不明白为什么我应该在这个编码阶段收到它。有人能在这方面帮助我吗？