i dont think you are telling us the whole sorry or you have a serious problem! 2 things cause mold, moisture and lack of air circulation. and there are 3 posibilities, 1 you have a plumbing leak, 2 a roof leak or 3 your growing plants in there or similar to cause that much damp. open trickle vents on window or regularly open window (common problem in bathrooms nobody open there window!) but personally i would be going up in the loft/attic and i'm almost sure your problem will be there. 1 last thing slight possibility of plumbing fault in wall/floor behind/below fitted robe. there is no point at all of using anything to cover/mask/absorb the problem, you need to get to the root of the problem