Skin and username change

After I updated my minecraft Java edition to 16.1, I've had constant problems with my skins changing and my username was randomly changed and I now am forced to wait to change my username back to what it originally was. I did not make any changes and I checked to see if my account was hacked but there are so signs of any hacking. Every time I open up minecraft it defaults me to a random new skin that is not a part of the default skins or any skins in my library. Is there anyway I can fix this besides having to wait to change my username and constantly reapply my skin?

Thank you for your time