why is minecraft asking me to change my username after updating the launcher?

Hello Lewcio , I am an independent advisor and I will be happy to help you today. My name is Khaji

Minecraft may ask you to change your username after updating the launcher due to several important reasons.

- Account Migration: Mojang, the company that develops Minecraft, has been migrating Mojang accounts to Microsoft accounts, During this process, you may be asked to change your username.

- Username already in use: If your username is being used by another account, you may be asked to change it

- Launcher Update: Some Minecraft launcher updates may require you to change your username.

This is not helpful, I am experiencing the same issue on an allready migrated account, the username is for THIS account.

Not sure why your Java username is showing as already taken, but since the Minecraft website shows that you own Java, this is probably just an issue with the Launcher syncing data.

Would you please try to reinstall Minecraft Java and the Minecraft Launcher too?

Then why when I open the Minecraft launcher after i changed the password I'm still logged in on my account and I didnt have to put the new password or anything

I am using the following website: https://hypixel.paniek.de/player/6538db5abf3a47a79f2f86b3057b350d/status to see that they are using my minecraft account to access the hypixel server. Furthermore, on my own side with my device, changing username, gamertag, password or using the force all sign out on microsoft security settings has not made my own minecraft launcher force me to sign in again, it simply uses the fact that its been logged in before and still lets me just press play and access any servers without a need to re-enter details. This seems like a vital security issue as a change in password should cause all minecraft launchers to sign out. Since then, I have also tried it on my friend's PC, where upon changing the password, it still allowed me to access my minecraft account from his launcher without needing to re-enter details there as well. For some reason the basic minecraft launcher does not require a re-entry of login details upon account password change.

Cheers