like everything else, a good first step is verifying power and connections and then isolate pieces to find the problem.
So, find out if you have a power assist pump. Look for a switch/breaker to power the pump. Follow the hoses to find the pump.
do you have 2 cylinders at the motors or one?
disconnect the tie bar from one and see what happens.
disconnect motors from the cylinder(s) and see if you can move them by hand. The bushings in the pivot shaft of a motor might be gummed up or just need grease..