Hello, it is an error that occurs when you start a world and you leave the game but do not close it. That makes armor invisible and a way to fix it by leaving the world and reentering.
MCPE-72935
armor bug when you get out of the game
Resolved
Duplicate
0
Thank you for your report!
We're actually already tracking this issue at MCPE-66451, so I 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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