Upon disconecting from other players' worlds, items such as Diamonds and stacks upon, stacks of iron have disappeared when returning to that world later on. I have tried looking for anyone else who have experienced these problems but found nothing. The strange part about this bug is that it only deletes paticular items; for example, diamonds, Gapples ( golden apples) and in this case, 3 stacks of iron ingots. As well as deleting items from my hotbar and inventory, items were deleted from my corpse where I had died. Me and my friend were joking around on his world and started to kill eachother. I killed him first and then he came and killed me. However when I died, the only items of mine that were to be found was my enchanted diamond armour. I had a full inventory mostly consisting of enchantment books and diamond tools as I had previously gone to enchant them on an anvil but got distracted. That entire inventory and hotbar of precious items were gone, and I was going to use these items to defeat the ender dragon and fully unlock all of the achievements. I am incredibly agitated and just want to make sure this bug is fixed and does not occur in the future for me or anyone else in the minecraft community.
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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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Did your friend knock you off a ledge and you died from falling? This can cause your items to fall through the floor/ground while your armor lands on the surface. We're tracking that issue at MCPE-48370.
If it's not too late, dig up the floor where you landed, or check any hoppers/hopper-minecarts under there or nearby.
The issue of reconnecting to a multiplayer world as a new player with empty inventory is being tracked at MCPE-55815.