I Have Been Diagnosed With Oral Thrush By Countless Doctors

I have been diagnosed with oral thrush by countless doctors since may of 2018. I have been on everything from a simple nystatin prescription, to a 2 week IV therapy via hospital using amphotericin B. I was sent away by my infectious disease doctor and told to get a biopsy done for "further testing", cause at this point there has been no positive test for Candida, as all these doctors I've seen positively identified my tongue as thrush by a visual exam. Has anyone ever heard of anything like this before, where symptoms completely resembled thrush but are completely unresponsive to any and all fungal treatments?