I am replacing a pair of shower cartridges on my 2 handle Moen shower knobs. I have disassembled the hot/cold handles, taken all of the pieces out and reinstalled the new cartridge into the pipe coming out of the wall and put back all of the remaining pieces. It seems pretty basic. Question, prior to turning on the water supply, I am turning one of the handle to the right to make sure that the water is turned off completely, prior to turning the water back on, and the knob will never stop turning. What is installed incorrectly? Thanks!