Need some guidance on this

Hi ladies I hope everyone is having a great day so I have a question I am 12 weeks pregnant during this whole process of this pregnancy I had a UTI My Obgyn had put me on Macrobid of course that didn't work so finally I decided to go see a urologist they have me on an antibiotic right now but I don't understand why the UTI is still around has anyone had this problem yet if so please let me know what I can do to resolve this problem this is my fourth medication for this type of UTI