Turn signal ground

[Muddemon]

All my light work when headlights are off including hazards, parking lights, brake, reverse and blinkers. When headlights are on though i cant get my right turn signal to work. I took the assembly off and cleaned. Also replaced bulb. The park light stays on and i do notice that one of the little prongs inside the bulb seems to blink low while the other stays on. I have a purple and blue wire that plug into that bulb from the opposite side. Should this bulb have a ground wire like my left side or does the assembly ground to the metal it connects to? My bezel turn signal will blink when lights off and stay solid when headlighrs on. Truck is 70 c10 stepside