.cls 文件中出现错误“未定义控制序列。”

Question

我正在使用 technojournal.clshttp://www.techno-press.org。当我在 overleaf 中编译主 tex 文件时，它显示错误

<recently read> \setremarkmarkup
1.904\setremarkmarkup
{(#2)}
The control sequence at the end of the top line
of your error message was never \def'ed. If youhavemisspelled it (e.g.,' \hobx'),type 'I' and the correctspelling (e.g., I\hbox'). Otherwise just continue,and I'll forget about whatever was undefned.

technojournal.cls中的代码如下：

    %%%%%%%%%%%%%%%%%%%%%%%%% refereee %%%%%%%%%%%%%%%%%%%%%%%%%%%%%
    \if@referee
    \RequirePackage{changes}
    \setremarkmarkup{(#2)}
    \pagestyle{journalstyle}
    \else
    \RequirePackage[final]{changes}
    \setremarkmarkup{(#2)}
    \pagestyle{empty}
    \fi
    \makeatother

我该如何修复它？