when you use mouse and keyboard on Minecraft console (ps4) and you go to your inventory and go out again there is a chance that your vieuw cam will go up or down.
and that happens almost every time.
this bug is also caused by opening chests.
this bug exists from the release of 1.16 (bedrock)
Thank you for your report!
We're actually already tracking this issue at MCPE-85000, 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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