I created a Microsoft account and played for a spell, until I changed my gamertag on the Xbox app—and subsequently made it so I can’t log in anymore. The error message says: “Failed to login: We tried to sign you in to your Microsoft Account, but something went wrong.”
I’ve tried every solution I’ve seen, contacted the Mojang Support twitter feed and emailed Mojang Support, and now am reporting the bug here. I am unable to crossplay or play online, rendering Minecraft essentially useless to me, now. Please fix this.