Help please Faullty wing mirrors on 330 sport convertible

[AFA]

Hi, my wing mirrors on the 330ci sport convertible 2004 model are not working properly. The nearside one moves in one direction only (UP) when I move switch up down or left & right and the off side one moves in downward position. Could it be the switch itself or has anyone ever had same kind of problem and is it best to take it to main dealers or an auto electrician. I would be very grateful for any advice. Thanks for taking time to read this,AFA.