Is it possible to overwrite accounts?

Hello, is it possible to overwrite an old account (PC) with creating an account (Xbox) with the same email? Because that's what I think happened to me. I bought Minecraft long ago then migrated and stopped playing for a long time because I went abroad (where I created a new account with the same email on an Xbox). Now my account for Minecraft isn't the old one and I have to buy the game again.

:)