Constant leaking ceiling? landlord won't fix, mold?

I live on the 6th (top) floor of an apartment complex. I have a slow leak from the ceiling. Basically water constantly but very slowly drips. There is about a 6 inch drywall type wall that seperates my bedroom from the living room. The water drips from the crease basically right where the wall meets the ceiling and slides down the wall leaving an ugly stain. This happened on both the living room and bedroom side of this wall. The first time the landlord claimed they fixed it the leak stopped for about a month and they painted over the stain. The second & 3rd time the leak didn't even stop for a day and they claimed it was fixed. I've reported it again. I don't see any mold but constant water flowing in is making me nervous. Do I need to worry about mold growing in the wall?