Did all this. . .
Microsoft Store - Download and Installation issues - Basic Troubleshooting – Microsoft Flight Simulator Support (zendesk.com)
(specifically resetting gaming services)
And. . .
This.
(And @OrigBullethead poured out a libation for the electro-monsters that prevent such things. 
)
And I think @TheSevenflyer linked those original “issues” in another thread, so thanks to him too!
Lastly, I can’t say for certain that all the things I tried actually fixed anything, as there is a good change that something was off on the server side of the house, and it just got squared away. 
Carry on.