Drs can’t figure out what causing vaginal itching.

I’ve had vaginal itching since May and I’ve seen my primary and a couple obgyns. All they do is prescribed me anti yeast stuff and say idk. I’m also testing negative for yeast so it’s not even that. I did just recently got through medical menopause (due to chemotherapy) however my cycle has been back to normal for several months now. I’m also Not/Never been sexually active. Any advice please 🙏