RCA Microwave Oven - heating but plate not rotating

Black RCA microwave oven. Includes glass turntable. Microwave works, but plate doesn't rotate. It makes half of the cyrcle and stuck. Because of that food doesn't heat up evenly. We used to heat it for a min and then rotate the plate and heat it 30 sec more. Pick up Beecroft rd (Sheppard x Yonge )