Either that or it may be kinked. It looks like your furnace is under the refrigerator. I would take the return air grill off the front and see if all the ducts are connected there. If it isn't a problem there, then you are probably going to have to get into the underbelly. Is it still under warranty?
Those ducts fittings, at least in our 250RS are circular and rotate to lock in the cover of the furnace. One of our came loose and our heat wasn't working correctly because of it. I took a pair of pliers and put a small bend on a tab of the connecter to help keep it from rotating due to vibration and reinstalled it. We haven't had a problem since then.