This bug has been around for years and has yet to have any attention paid to it in spite of skins literally being something you sell.
Repro steps:
Have a skin that you have customized in any way through the Dressing Room feature.
Open the Windows Store version of the game.
See that your skins are there if you enter the dressing room.
Play the game for any length of time.
Exit to the main menu
See that your current skin has reset to either the default Alex or Steve skin
Open the dressing room
See that ALL OTHER SKINS have been reverted to default Alex or Steve skins
Open Minecraft on a shared platform (Xbox, Switch, etc.)
See that the game has saved its changes to all of your skins to your account making the entire feature pointless.
One would think after enough of these reports have been made and with YEARS of development effort, this bug would be gone by now, but no. No idea what is going on over there, but we have reached new levels of absurdity with this one.
It would be one thing if this were some visual glitch on the Windows client not loading or rendering the skins properly, but no, you are literally resetting the entire skin back to default AND SAVING THE CHANGES ON THE SERVER SIDE.
For the love of God, just fix this thing. You literally sell skins and yet you have your character system in this state of complete disrepair and non-functionality. And just so we are clear this happens with both fully customized Dressing Room character skins and Classic Skins. Does not matter.
Related issues
Comments


No, at no point was I offline during this process. This is a similar bug, but not identical to the linked one. I do not see the "Failed to load character" message at all on either platform, and this issue shows up directly on the first client with no change in platform needed. (I have encountered the linked bug, also, and mostly seem to experience that one on the Switch platform.)
I would expect changes to an offline profile to behave the way you are describing, but what I am seeing is the exact opposite of that. At game launch, the online profile is loaded properly with the skins created as expected. After saving and exiting from the game session and returning to the main menu, not only has the current skin been reverted to a default state, so have all other created skins on the account. And then, just to prove that this has all been done while online, those reverted skins are saved to the online account and can be seen as the "new" reverted to default state on all other platforms, as opposed to simply showing the "Unable to load character" error message if it were experiencing network issues for whatever reason.
This bug actually fully reverts character skins and saves them to the online account, without the player's action or permission.

This may have happened to me. I lost all of my customized characters on two accounts this week. Each account is usually only used on one computer, one is occasionally shared between the devices. I left a comment describing on MCPE-53398 because I'm not sure whether they were lost between loads of the game (that bug) or while the game was running (this bug). The reset of all my characters seems to coincide with a character creator UI update that was pushed out on June 1.

Thank you for your report!
However, this issue has been temporarily closed as Awaiting Response.
Is this still an issue in the latest version? If yes, can you please add it to the affected versions (or mention it if you are not the reporter)?
This ticket will automatically reopen when you reply.
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Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.
For any account or purchasing related issues, please contact Minecraft Customer Support directly, as we cannot assist with those here at the bug tracker.
Quick Links:
📓 Issue Guidelines – 💬 Mojang Support – 📧 Suggestions – 📖 Minecraft Wiki
Does this only happen if you start the game without internet connection, or lose connecting while playing?
In my experience the game saves an offline profile that it sometimes loads when you are offline or if you are already logged in on another device. If you edit your character/skins while "logged in" to the offline profile it will not save them to your MS account profile and vice-versa. (This may be what MCPE-89591 was trying to report but the description doesn't really cover it.)
Alternatively, could what you're experiencing when switching devices be explained by MCPE-151642?