Same thing happened to us yesterday. In fact, a week or two ago, we went to get into the Fastpass line and they told us we didn't have any Fastpasses. Had to bring up the app to show them, which of course is the slowest loading app so everything grinds to a halt while I have to load my Fastpass as proof. Happened yesterday too, then we were told about the "technical difficulties" when we went for our 4th Fastpass at the kiosk. 1 Fastpass - all Magicbands in the party had to be present at the kiosk, and we could only get 1 Fastpass and could not change the time or attraction if we changed our minds. Such a great way to make vacation planning easier, right?
And don't get me started on when I reached the limit on days I can book because of limitations. Have dinner reservations 1 day and 2 weekends (in which we're staying 2 nights) while my wife's and my parents are in town in the next few months, but too many days for the system to allow.