Cross-referencing issue with subcaption in beamer

Question

Thank you in advance and support that provides this website for the tex users. I am a new member of the tex society almost a year now and I can say that most of my answers related to my problems have been answered previously here. Your work is really impressing taken in consideration that people are sharing knowledge for free.

Recently I came across with a problem that I think it is a bug of the system. I was trying to create a beamer presentation and by using \usepackage{subcaption} and \begin{subfigure} environment. While I was trying to use the \label and \ref points to my subfigure(s) I noticed that only the first \label was operating correctly as 1a. Unfortunately the rest are coming up as ??. I assume this is because the \ref points are located before the \label, but in this case all of them should not be operating correctly all should fail.

I was not able to find an answer relative to my question no matter how much I searched for. Maybe it is a bug of the system. I was just hopping that you could provide more information and maybe a solution to overcome this problem.

More information and the testing code can be found here: Multiple \label commands before \ref.

\documentclass[xcolor=pdftex,dvipsnames,table]{beamer}
\usepackage[english]{babel}
\usepackage{hyperref}
\usepackage{cleveref}
\usepackage{caption}
\usepackage{subcaption}

\mode<presentation>
\setbeamertemplate{caption}[numbered]

\begin{document}
\begin{frame} 
\begin{columns}[t] 
\begin{column}[T]{5cm} 
\begin{itemize} 
\item<+-| alert@+> 1~\autoref{1} 
\item<+-| alert@+> 2~\autoref{2} etc 
\end{itemize} 
\end{column} 
\begin{column}[T]{5cm} 
\begin{figure} 
\only<1>{\begin{subfigure}[b]{1.0\linewidth} 
         \caption{sub caption 1} 
         \label{1} 
         \includegraphics[width=7.0cm,height=5cm]{fig 1} 
         \end{subfigure} } 
\only<2>{\begin{subfigure}[b]{1.0\linewidth} 
         \caption{sub caption 2} 
         \label{2} 
         \includegraphics[width=5.5cm,height=5cm]{fig 2} 
         \end{subfigure} }
\caption{main} 
\protect\label{3} 
\end{figure} 
\end{column} 
\end{columns} 
\end{frame}
\end{document}