Itching/pain/irritation down there (not yeast or std)

I’ve been having external itching, some pain, and general irritation down there for over a month now. I’ve been to my gyn and been tested for yeast and all STDS along with other rare bacterias, all negative.

We still treated it as yeast, and the symptoms resolved for a week before coming back. Then we tried a steroid crème mixed with an antifungal, kinda worked, but not as well, with symptoms still coming back. The area is a light red, no bumps or sores, just red and irritated.

Both I and my doctor are quite stumped at this point. She doesn’t think it’s yeast and neither do I, it’s all external in the highlighted area. I’ve stopped wearing panty liners, only worn cotton underwear, made sure to rinse it only with water in the shower (no douching), not changed any detergent and made sure it’s fragrance free. It does move around a bit overtime, even though it’s mostly focused in this area, but it’s solely external not internal.

Has anyone experienced anything like this? My only other ideas is that it’s eczema (my doctor mentioned this awhile ago, I’ve never had it but I do have sensitive skin), possibly stress related, or maybe it’s something urinary and I should get that tested (I have no pain while urinating though). Or maybe I should see a dermatologist instead about it? It’s just super odd and figured I’d ask if anyone has gone through a similar thing. Any help or advice would be much appreciated! :)