ivan,
There is a fuse board under the top cover of the operators platform. Remove the cover and the cover over the fuse board, up against the front plate. Check all fuses to make sure they carry voltage with lift turned on. If fuses are good, checked all wire connection at fuse board and contactor. Also check contactor coil for resistance, should read about 32 to 34 ohms. You will probably find a bad fuse. Good luck
I have the same problem now in 2022. Did you manage to fix it?