Right blinkers work but only tail light blinker works on left

[71gmcC15]

Im new to the forums so dont bite my head off. I have a 71 gmc c15. I have looked for this in the seach fountion and could not find any thing. The right blinkers work fine but the left only the tail light blinks . Slowly i may add. It also dont have the green arrow on the dash when i go to use the left blinker. Same with hazzards. High beams does not affect it. I dont think its a ground but maby. It some times works. Like 5% of the time. It also has a new relay and hazzard swich. No bulbs are burnt out. So im cunfused