Bathroom Ceiling Fan Ducting Problem

Hello I'm having some difficulty in identifying the correct trades person to deal with our problem described below. The lists of "What do you need help with" do not seem to cover it. I believe it may be an electrician but do not want to waste anyone's time by an incorrect selection. Can you please point me in the right direction? Thank you in anticipation. ------------------------------------------------------------------------------------------------------------ PROBLEM The extractor fan fitted into the ceiling of our en-suite is showing a damp stain around it and water will drip down on to the floor from the fan. The fan is working normally. The suite has no window, so the flexible duct connected to the fan rises vertically in the loft and goes out to the top of the gable end wall. We would like the problem addressed by fixing the existing system or an alternative option provided.