Rega p5/ Dyn 10x5 problem

I just set up my Dynavector 10x5 on my Rega P5. I installed the 2mm shim under the tonearm. When I move the arm back to the position that should lift the tonearm/ cartridge off the record it does not clear the record. The platter is in proper position. The part of the tonearm assembly that raises to lift the tonearm is working properly. I have to manually raise the tonearm off its cradle to set the cartridge on the record and then again to set it back on the cradle.
Any help is appreciated.