IUD for sixth months- BV

So basically I got the Mirena on Halloween of 2018 and the first month was bloody, but then I was fine for two awesome weeks. The I got what I though was a UTI, but the results came back negative. I have a need to pee, burning urine. Itchy and burning vagina, and a smell. The symptoms come and go and I feel normal about every two weeks for 4 days. Then it all comes back. It’s ridiculously uncomfortable, and have made me exhausted. I don’t know what it could be, I’ve been tested for UTI, yeast infection, and all sorts of other things. But it’s been a constant bother and I have been to my OBGYN so many times and I don’t know what to do.