DSH 20121 Mirrored bypass door part

I don't know the vintage of the home, probably 90s but There are sliding mirrored bypass closet doors in my bedroom. The track seems just fine but the rear door pops off the top railing. I think this is caused by the mounting of the hardware. It appears to not fully sit in the track as does the hardware of the front door. The upper hardware bears the number: DSH 20121. Does the upper hardware need to be replaced with an improved version to keep it from popping out of the track or do I just need to adjust or remount the current one. If a replacement is needed and there's one that the doesn't require drilling another hole in the door frame I would very much appreciate. Several photos are attached.