How can I mend my Stannah 260 stairlift no green light on?

The stairlift did not move to top of rail and it did not charge. Green light came on but yellow light did not. Used hand crank to move to charging position and battery charged. When battery was fully charged. Now the yellow light is on indicating that the battery is charged but the green light will not turn on and the lift will not move. How do I fix this problem.