I taxed it last time on the green slip but apparently that doesn't throw up any flags saying the car has changed they wait until the log book arrives from the old keeper.
So my cheque was good enough last time and it was accepted with my address on the form I filled in but the DVLA still have the old Keepers name there and they are digging in their heels I cannot use it while its sorted out and I can't tax it until its sorted out.

the new DVLA rules are

the old method was better.
Edited to add I was on the phone for 30 mins as far as they are concerned I am not the registered keeper so its 4 to 6 weeks....