Same issue here.
I think i fixed it by changing my email in the registry too:
- Press Windows Key + R
- Type regedit and press OK
- Press F3 and search for your old email
- It may show up a few times, so press F3 again until the Xbox related one, comes up.
- Change it to your new email,
- Close the Window and reboot computer
What an annoying BUG! .. Microsoft.. yes, looking at you!