Turn signals on the side of the fenders not working

So my side turn signals (the ones on the left and ride fenders) aren't working. I've replaced the bulbs and all my fuses. All my other turn signals work, but those ones don't, so whenever I use my turn signals all the functioning ones just flash really fast.

Any ideas at this point? What else can I try? I have another turn signal switch, but I have a feeling that's not the problem.