Im having the same problem, my rig was rented from user "tomdif" for 24 hours,
The renter never used even if i had emailed him. The rent has been over and the service still is showing "Rented - Ends in 1 day".
So i desided to disconnected it from the betarigs pool and still shows "Rented - Ends in 1 day".
I think all the rigs the user "tomdif" have rented have the same problem.