mtd yardman - hydrostatic bypass not working

hi
recently got a yardman lawn tractor. the bypass lever will not put tractor into neutral. also when I try to drive it seem transmission is locked and tractor wont move forward.
bypass has worked in the past but has quit for some reason. it has a hydro gear transaxle. is this problem fixable. unit has been in storage for a year. with no known cause
of problem.
thanks for any info.
mike

Remove the right rear wheel and check the brake.
Most likely it is rusted on preventing the layshaft from turning locking the diff.
When the rear is up in the air turn one wheel if the other turns in the opposite direction, the brake is locked.
While you are in there, clean & grease the axel to preventing the wheel rusting solid on the shaft.