Brake/parking light issue

[Angrywood]

Straight to the point….. the driver side tail light works….parking light and the brake light. Both filaments light up in the bulb as they are suppose to. The passenger side doesn’t. The same filament lights up when brake is activated or when parking light is on. However if break is activated when the parking light is on…light goes out. I have switched the bulbs from one side to the other and the same thing happens.

I ran new wiring harnesses from the cab back and it used to work right. Now it is not after i have connected everything after putting the bed back on. I now it is probably something super simple im over looking but cant figure it out. Any ideas for me? I feel stupid for even having to ask this but its better than having to take it to a mechanic. Thanks for your input