You cannot join Realms if your username starts with underscore

Put the summary of the bug you're having here
I tryed with 2 accounts:
1st called: "Hovedpude"
2nd called "_Jonathan"

I bought a realm and i cannot join the realm but i can join every other server on "_Jonathan". But on the same machine i can do everything with the account called "Hovedpude". Ive tryed to sign in and out but it dosnt help. Both accounts are Microsoft.

What I expected to happen was...:
I expected i could join my own realm with my account named "_Jonathan"

What actually happened was...:
I get an error called: Internal Exception: java.net.SocketException: Connection reset

Steps to Reproduce:
1. Buy a realm
2. Join realm on an account with a name starting with an "_" (And get the exception)
3. Join the same realm on an account named anything else and you should get in.

P.S.

Ive attached 2 Logs. The one called "latest.log" is the one that cannot join.
The other called "2022-06-07-7.log" is the one that can join