Last week I fitted some floor to ceiling MDF wardrobes I made for a customer, total being 3300 wide in three sections and 2300 high. I had them professionally spray finished in white. They look great and the customer said so but, they won't pay the balance as a couple of the doors are about 2mm out at the top which unfortunately isn't unusual for tall MDF doors. I've tried but adjustment has no effect. I know that over time the pressure from the hinge side can help them go completely flat. Any other customer wouldn't give it a second thought because it really doesn't notice, but they are fussy to the point of being ocd. Any suggestions as to how to proceed?