ᐅ Pax IKEA wardrobe system / Lyngdal wardrobe doors, front door is scraping

For a few days now, the front of the two doors has been scraping. The rear one still slides perfectly. After checking, to the best of my knowledge, I could not find that the door is off its correct tracks at the top or bottom. Does anyone have a tip on where I should look for the problem?

It still sounds like the door has come off its track.