Here are some reasons for your PAX wardrobe malfunction
First, most likely, something has come loose. Thoroughly check the hardware and go around giving them half a turn or till it feels firm (but do not over-tighten). If the bolts are loose, the joints will disengage from each other.
Don’t forget the backer board at the back of the wardrobe. It may have come loose from the groove and is causing an imbalance.
Secondly, check whether your flooring is level. Uneven flooring may cause the frame to sag on one side. The PAX comes with adjustable feet, so do adjust them to support the frame uniformly.
Thirdly, the shelf or drawer has sagged. If you’ve placed really heavy things on them, they will sag and fall off the dowels. But this doesn’t seem to be the case for you, as you’ve noticed the frame has moved outwards.
Another possibility, the frame has bulged because of humidity or water damage. If placed near a water source or if you hang a wet towel on the PAX frame everyday, it will cause the particleboard to warp, over time.
So try the above methods and let us know how it goes.
If none of the above, you could be one of the unlucky ones to get a defective unit. In that case, you can apply for the PAX 10-year limited warranty. Ask you local IKEA Customer Service about it.