Try CTRL+R, %appdata% and if u have some world or ResourcePack, save it,
 (And then delete .minecraft).
Then next, reinstall Mincraft Launcher (From web profile).
I have the same issue
Liam, i have the same fvckng problem u have. Do u resolved it yet?
Same issue, you need to Create a Ticket, from help.minecraft.net/new (Microsoft Support, if MOJANG don't do nothing in days talking with him).
If you keep with the problem, maybe try with a new ticket to help.minecraft.net (AGAIN)
(If the Game was not migrated correctly. TALK EVERYTHING TO HELP MORE FAST!)
And... not need to wait like 1 month typing to (NOT YET) resolve the same problem.
Go and do the ticket, or you will not able to play. (Like Me 🙂)