how do i repair my turn signal switch for my high/low beams? on 1993 Chevrolet Lumina APV

im driving and my headlights cut off. my high/low beam light switch is located on my turn signal switch. i have to pull it forward to go from low-high beam. i pulled to turn to low beams on and the switch wont catch or hold. it sometimes clicks and stays on and sometimes doesn't. i now have to drive holding the steering wheel and turn signal switch on at the same time. trying to drive and keep the switch pulled forward is difficult. what is the problem?

they call that a mutifunction switch,and it is possibly going bad inside the assm. have it ck'd first by your mech to verify b4 changing it.