I just factory reset my Amazon Fire and re-installed Minecraft, now it get's stuck on " Signing in with your Microsoft Account", but it doesn't prompt for my login info.  If I press Cancel, I get:

Failed to login

"We tried to sign you in to your Microsoft Account but something went wrong".

There is just a "close" button.

If I try to click "Sign In" again, it immediately fails with the above message again.

I've also tried going into Settings | Profile | Sign in for Free! ... same issue ... gets stuck on "Signing in with your Microsoft Account".

I've tried "Clear Account Sign in Data" ... clicking on that turns the button green, but doesn't appear to do anything.

Other things I've tried:

Clear Storage / Cache

Uninstall and Re-install

Reboot tablet.

I'm out of ideas.