When you open the “Minecraft” app the skin always resets to default(Steve or Alex). You have to enter the skin selector in order to set your skin in the one you wanted.
Another report has been made but there it states that the bug is Resolved
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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.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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