Logged into wrong X-Box account after account migration from one Microsoft account to another

Was faced with a very specific issue today which involves me being locked from using any games associated with my X-Box account. In order to explain the issue, it is best to describe a timeline of events and using the example game Minecraft:

1. create a Mojang account and buy Minecraft (long ago)
   
2. successfully migrate the Mojang account to a Microsoft account associated with the same email address A as the Mojang account
   
3. Create a new Microsoft account for unrelated reasons with email address B
   
4. Create X-Box profile associated with Microsoft account registered to address B
   
5. Migrate (merge) account registered to address A into account registered to address B
   
6. Delete leftovers of account associated with address A
   
7. Try to log in to X-Box account which I assumed to be merged as well
   
8. Can only log into X-Box account originally associated with address B
   
9. X-Box account originally associated with address A is inaccessible
   

A screenshot may help to illustrate the issue better (directly inserting an image here fails):

https://imgur.com/a/EC8udrK

You can see the old account A as username "bruh20631" and the newer account B as "Dismuetre". "Dismuetre" does not have a valid license of Minecraft, but "bruh20631" does. However, since the underlying accounts were merged and account A deleted, logging into X-Box with my address B now always takes me to profile "Dismuetre". Any games associated with profile "bruh20631" are now gone. Trying to manage anything concerning "bruh20631" leads me to the "Dismuetre" profile.

Please note that this is NOT about a migration from Mojang to Microsoft, this is an account migration from Microsoft to Microsoft. Also note that account A is gone and irretrievable. All I want to do is claim back the games that I paid for. Support for such an issue is apparently not easily available, which is why I'm asking here.

:)