OP here...
Called in mid-rental to make a change to the drop off.
Phone agent keyed in my RA# and said “hmm... that agreement is showing as cancelled. Can you read me the VIN?”
She was able to make the necessary changes after working around in the system for a few minutes. She couldn’t explain why the agreement was cancelled.
One instance of this is an anomaly. Now it’s happened during 2 of my last 3 rentals. Different locations, different vehicles, etc.