I must be a pariah.
We started receiving emails again, then they updated the app.
We were still getting emails when I tried to send one.
Outlook, not the provider, said, "I wasn't authorized".
It started making me login for everything, over and over.
Finally, it quit getting emails.
I un-installed it and resigned myself (like so many others) to using my providers email system.
Who knows, maybe MS will fix this some year.