Top drawer has suddenly become very difficult to open and close. Front 1/3 of the drawer is hard to open, middle 1/3 glides normally, and final 1/3 becomes difficult again. I'm reluctant to apply a lot of pressure for fear that I will break something. Have removed the tub to check the but upon reattachment, problem still persists. Noticed that the Moisture Protection Tape area seems to be a little floppy, gives a little. Any assistance would be appreciated. Thanks, Ed