how long do i have to take boric acid?

so i’m having a problem with my bv reoccurring. no matter how i take boric acid, first the instructions said once a night for seven days. cool did that and BV came back. tried it twice a day for 5 days, seemed like everything was going good then it came back. going off instructions didn’t help, and online it says i might have to take it for 7-14 days or maybe even up to a month. my question is how would i know when i could stop taking it? symptoms were clearing up within 2 days taking it twice a day yet it still came back i’ve been living with BV since november seems like nothing is working 😞 also what about taking it on my period just in case my period is also throwing off my PH balance cause by the time i do treatment twice it’s time for my period again..