Zero Turn Mowers

Aloha, We have a Z4218 zero turn mower. I used the mower and put it away last week with no problems. Today I pulled the two drive release rods in the back of the mower and released the parking break, pulled the mower out of its parking spot as always and re-engaged the brake and drive rods. The mower starts but won't go back into drive mode. When I move the mower control arms nothing happens, but I cannot push the mower even with the brake of so it feels like it's engaged. No sound change when controle arms are operated ether. Belt is fine and in place, deck operates, break off or on doesn't matter. Mower won't move. Help Stokes.