Unable to log on my Microsoft account though Steam.

Hello !

I'm currently having a lot of issues with my microsoft account, so I'll try to summerise the context before stating my current problem :

Earlier in 2022 I bought a new gaming/working computer and with it some games, including Sea of Thieves (that I bought on Steam since that plateform regroups most of my gaming library). Prior to that, I had made a Microsoft account to replace the former Mojang account that was required to play Minecraft, so I linked that account to my Steam account. I played a couple of months without issues, until last Summer. Then after an update, my account got signed out so I naturally had to input my password, but it didn't work. So after a couple of failed attempts, I tried to send a password reset but the mail adress was nothing alike any of my mail adresses. Then I tried to fill the account recovery form to get my account back, considering that it probably got hacked, but when it came to fill transaction informations, I couldn't give relevant infos, since every Microsoft product I bought was never directly bought from the Microsoft store. In the end I could never recover my account and with it, my games (which is really unfair considering I bought them, but one on Steam, the other on Mojang's website before it was bought by Microsoft).

So today I thought that maybe I could buy Sea of Thieves again, from another Microsoft Account. But the issue is, that on Steam I can't log in to the game using my new Microsoft account. Even if I sign out my former hacked account, and try to connect my new account (the one I'm currently posting this question with), I get a message that says "You must be signed in on Xbox Live to play Sea of Thieves. Please Sign in and try again. (Ashbeard)", but the thing is : I'm actually signed in the Xbox App and I'm even downloading the game directly from there to at least see if it even works. And if I try to redo the operation, I can se my account in the Pick an account window, but there is a message that says : "That Microsoft account doesn't exist. Enter a different account or get a new one."

So now for the actual question :

First : Is there a mean for me to get my former games back (the hacked account was : *** Die E-Mail-Adresse wurde aus Datenschutzgründen entfernt. ***) ?

And secondly : Is there any way I can play on Steam using the supposedly working new account ?

Thank you for your answer (and sorry for the bad english, I'm french)

:)