Steps to reproduce:
Have a custom skin pack
Select a skin from it
Quit the game and enter again
Expected results:
The skin is kept when reopening the game.
Observed resulst:
The skin resets to either Steve or Alex.
Note that this is only with custom skin packs, marketplace packs and custom skins still work properly.
Related issues
Comments

Thank you for your report!
We're actually already tracking this issue at MCPE-32089, so we will resolve and link this ticket as a duplicate.
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