Vulvar acne. Bigger in size and painful.

I am a 23 yr old female. I have been suffering from a chronic vulvar acne condition from past two years. At first there was just one or two acne which disappeared after few days. Then as the condition got worse I visited a gynaecologist and she prescribed some oral antibiotics and a soframycin cream . I applied it for fews days. And after that I got relieved. But after some time acne apperaed acne with the time healing time or acne increased and I got multiple acne on my vulva, after that I visited a dermatologist who again prescribed some antibiotics and a antibacterial cream. Acne gets worse as my periods are near and after my periods are over they last for many days. Now the acne are bigger in size and painful.