If I had to guess, given that you've tried other treatments, I'd say you could have a yeast infection (which wouldn't likely respond to the jock-itch cream).
Also, if it IS a fungal infection, you may have to try several different creams or sprays, with different active ingredients. There are quite a few, and most are over-the-counter. I had a fungal infection on my skin that I treated with the active ingredient in jock itch cream, and it did almost nothing. I switched to the one for athlete's foot, with a different active ingredient, and that worked a charm.
Here's a list of some of the common anti-fungals: https://www.nhs.uk/conditions/antifungal-medicines/
I totally agree with Curfew.
The only other thing is that even if you haven't changed any products, have any of your products changed formulas - think "new and improved"? Have they added a scent to it, or have you changed scents?