[Tex/LaTex] Undefined control sequence error with $\inst{}$ inside \author

Question

I am writing a journal paper using Springer template and I am trying to use \inst and \institute to add different affiliation for one author. However, I couldn't solve the error "! Undefined control sequence".

I have tried different solution mentioned in this website but non is working for me. The following example will occur the same error

\RequirePackage{fix-cm}

\documentclass[smallcondensed]{svjour3}     

\smartqed  
\usepackage{graphicx}
\usepackage{authblk}
\usepackage{pbox}
\usepackage{commath}
\usepackage[numbers,sort&compress]{natbib}
\usepackage{rotating}
\usepackage{algorithm2e,algorithmic}
\usepackage{epstopdf}
\usepackage{longtable}
\usepackage{tabularx,ragged2e,booktabs}
\usepackage{graphicx}
\usepackage{color}
%\usepackage{apacite}
\usepackage[misc,geometry]{ifsym}
\usepackage{amsmath}
\usepackage{url}
\usepackage[margin=1in]{geometry}
\usepackage{mathptmx}  


 \journalname{Journal Nmae}
%
\begin{document}

\title{Insert your title here
}
\subtitle{Do you have a subtitle?\\ If so, write it here}

\author{AuthorA  $^\inst{1,2}$   \and
        AuthorB   $^\inst{1}$ \and
        AuthorC  $^\inst{1}$ 
}



\institute{F. Author \at
              first address \\
              Tel.: +123-45-678910\\
              Fax: +123-45-678910\\
              \email{fauthor@example.com}           
           \and
           S. Author \at
              second address
}

\date{}



\maketitle


\end{document}

Answer 1

The svjour3 class doesn't use superscript numbers to identify the addresses.

\documentclass[smallcondensed]{svjour3}     

\usepackage{graphicx}
\usepackage{authblk}
\usepackage{pbox}
\usepackage{commath}
\usepackage[numbers,sort&compress]{natbib}
\usepackage{rotating}
\usepackage{algorithm2e,algorithmic}
\usepackage{epstopdf}
\usepackage{longtable}
\usepackage{tabularx,ragged2e,booktabs}
\usepackage{graphicx}
\usepackage{color}
%\usepackage{apacite}
\usepackage[misc,geometry]{ifsym}
\usepackage{amsmath}
\usepackage{url}
\usepackage[margin=1in]{geometry}

\usepackage{mathptmx}  

\journalname{Journal Nmae}
\smartqed  


\begin{document}

\title{Insert your title here}
\subtitle{Do you have a subtitle?\\ If so, write it here}

\author{AuthorA \and
        AuthorB \and
        AuthorC 
}



\institute{%
  AuthorA \and AuthorB \and AuthorC 
  \at
  first address \\
  Tel.: +123-45-678910\\
  Fax: +123-45-678910\\
  \email{fauthor@example.com}           
  \and
  AuthorA
  \at
  second address
}

\date{}



\maketitle


\end{document}

The arrow in the picture represents the text, the institutions will be at the bottom of the page.