I had a set of waterfall bath taps fitted and after only 14 months the water flow has reduced significantly. There is a filter fitted on the spout of the tap with 2 screws underneath, can these screws be removed to clean the filter without turning the water off.
Since you didnt see fit to say what the make and model are, how in Earth do you expect us to be able to search for the manual, read it and post a simplified version for you to read?