Heater Fan Switch works, then it doesn't

So if one day my heater fan switch works fine and the next day it doesn't, does that mean I have to replace the switch? Or can I just do something to repair the switch? Anyone done this? Sometimes I have to switch it to the fast speed, then back to the slow speed for it to turn on.

My switch does this too. I had to take it apart and clean it out.

it could also be a not so good connection where the wires join together at the heater motor.