I want to fix this diagram and also extend it to the diagram below. Can you help me out?
$\require{AMScd}$
$\begin{CD} S^{n-1}@>\subseteq >> D^n \\ @VhVV @VVV\\ S^{n-1}\\ @V\subseteq VV @VVV\\ D^n @>>>\Sigma^n(h) \end{CD}$
The 'double-down-arrow' on the right side of the diagram is supposed to be just one arrow, but I did not manage to fix this. I am not familiar with constructing those diagrams. I am thankful, when someone fixes it, or tells me how to fix it.
Thanks in advance.