Hi guys, I unscrewed the metal drainer in my bath to clean behind it (it was draining very slowly). I have tried to rescrew the drainer back in place, but the screw hole is attached to a black plastic tube/pipe which gives way and moves down when pressure is applied to it. I have tried to hold the plastic thing in place whilst rescrewing the drainer in place (with wire through the holes of the drainer) but it doesn't work. Can someone tell me what the black pipe/tube thing is and whether I need to take the panel off... Or shall I call a plumber? Thanks - A Girl!