Talk to Dermatologist on Pitryasis Versicolor/Ashy Dermatosis

Salam Dr. Ajmal. I have several white spots and greyish patches on my face for the past 8 years, I consulted many dermatologists and every one of them had a different POV. Some said it's vitiligo, some pitryasis versicolor, and some said ashy dermatosis, I even went for skin biopsy at Aga Khan but they denied doing face biopsy, I am very very confused and it really makes me cry looking at my face in the mirror. Can you please help me