Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!
Year model? Where is the F/R switch? At your right knee or a switch on dash? If you have the knee switch, the F/R switch is likley the problem, as that is where the direction change is made. You can swap F/R cables on the switch to see if it swaps problem. If it does, replace or repair the switch. If you have dash switch, the change is made in the controller and the controller is bad.
I see question is still open, did you see my response?