如何使用AAS中的子标题包（例如apjs模板），为什么使用时会出现标题标记为红色的错误？

Question

\begin{figure*}
  \centering
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (a).pdf}
    \caption{Noisy full-disk image}
  \end{subfigure}\hspace{1em}
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (b).pdf}
    \caption{Local zoomed-in image of noise image}
  \end{subfigure}
  
  \vspace{1em}
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (c).pdf}
    \caption{SEID full-disk image}
  \end{subfigure}\hspace{1em}
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (d).pdf}
    \caption{FFT-wavelet full-disk image}
  \end{subfigure}\hspace{1em}
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (e).pdf}
    \caption{1D-GF full-disk image}
  \end{subfigure}\hspace{1em}
  \begin{subfigure}[t]{0.23\textwidth}
    \includegraphics[width=\textwidth]{Figure 2 (f).pdf}
    \caption{WLS-BF full-disk image}
  \end{subfigure}