I suppose in time those roller wheels can wear out but:
Most likely the track at the floor is just dirty and in need of lubrication.
You might be amazed at the difference if you simply clean the track, then rub "Door Ease" Lubricant once or twice along the top edge just where the rollers touch the track.
Hardware stores carry it. It's like a big red crayon.
AGSŪ Door-Ease Lube Stik (DE-2) - Lubricants - Ace Hardware
Sorry, sliding glass door repairmen.