Passenger electric headrest not working

My passenger side headrest won't go up or down. I can hear the motor running but it's not moving. I could pull it up a little by hand while depressing switch and it would move a little but making a slipping gear sound. I pulled it out depressing button on back of seat and reincerted it and now it doesn't do anthing. No clicking sound but I can still hear motor running. How do you fix this? Dennis