# Unnumbered subfigure captions with line stretching

I'm trying to caption some subfigures with a label, but I'm also trying to slightly stretch the text of the subfigures. It seems when I apply these two pieces of code together, I get an error. Can anyone see what I'm doing wrong?

\documentclass[12pt, twoside]{report}

\usepackage{caption}
\usepackage{subcaption}
\captionsetup{font={stretch=1.3}} %This appears incompatable

\begin{document}
\begin{figure}
\begin{subfigure}{\linewidth}
\caption*{Unnumbered sub-image caption} %This appears incompatable
\end{subfigure}
\end{figure}
\end{document}


Solved it. I forget to add the package {setspace} at the beginning.

\documentclass[12pt, twoside]{report}

\usapackage{setspace}
\usepackage{caption}
\usepackage{subcaption}
\captionsetup{font={stretch=1.3}} %This appears incompatable

\begin{document}
\begin{figure}
\begin{subfigure}{\linewidth}
\caption*{Unnumbered sub-image caption} %This appears incompatable
\end{subfigure}
\end{figure}
\end{document}