Hi there, I have a S reg mk4 golf (5 door hatch) and i have a slight problem....yesterday, i was slightly heavy handed and snapped off the wing mirrror electronic adjustment knob on the drivers door whilst trying to adjust the mirrors .... can anybody tell me what i should do here and more importantly what it will likely cost me to fix

annoyingly my left mirror is out of line and i cant maunally adjust it either (to my knowledge)
any help would be greatly appreciated