The bug:
This bug happned for some days. In my world , Iplay with my brother. He is player 2. He isn't a Bad player so he had very good things in his Inventar. Than we went offline.The reason was a not really import acitent , so we couldn't go online. Player 2 spawnt at our Worldspawnpoint and he has no XP and things. So he lost bis Inventar. Some days later we went online and he had the Inventar bevor we went offline.
So you reproduce the bug'
1) Go in a world as a second player
2)Do some things in your Inventar like a stack Earth vor get some XP
3) Left the world
4) Go offline
5) Go again in your world AS second player
6) so you lost the stack earth or the XP
7) left the world
8) go online
9) go in your world AS second player
10) So you schould have the stack earth or the XP
This bug is not at player 1.
The bug only work at consoles on the TV
(Sorry for my Bad englisch. I normaly talk german )
Related issues
Comments

We are still looking into the issue with player data changing or being lost at MCPE-55815.
If the issue is still occurring for you in the latest version (currently 1.16.1) please could you add any steps to reproduce the issue at MCPE-55815.
Also, if you have a copy of the world save available, you might like to share a copy of it for investigation.
On Windows 10 you can use the Export world feature.
On Android or iOS you need to use a file explorer to navigate to Device storage > games > com.mojang > minecraftWorlds
On Xbox or Switch the only way is to upload it to a Realm, and then download the world on Windows 10 or Android/iOS. (Please do not purchase a Realms subscription just to provide a world to us - but if you have a Realm already this may be a viable option if you wish to do so.)
If the world is larger than 10MB you can upload the world to OneDrive or a similar file sharing site, and then share the link in a comment at the main bug ticket at MCPE-55815.
Thank you for your help, and for your patience while we look into this bug.
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Thank you for your report!
We're actually already tracking this issue at MCPE-55815, 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.
If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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