bra strap itchching

I wear cotton bras mostly and off late i developed itching on my back where the strap hooks. I work in an airconditioned area so i dont sweat much but the itchching persisted for sometime and i was rather comfy wearing saree because i unhooked my bra during the late afternoons which immediately stopped the itch but that cant be a regual r feature at work as i might have to leave my cabin sometimes.
I went to my regular doctor and he prescribed me Zole-F as he told me that it was fungal infection. I even washed my bras in hot water hoping that what ever fungal infection was there would go off but it looks like the itch persists. pls suggest what can b done? is it advisable to minimise the use of bra at home to avoid any sort of skin infection? is there any other remedy? any help would b highly appreciated. thanks all.