I Currently Have The Mirena Iud. It Was Reinserted Late

I currently have the mirena iud. It was reinserted late July. I currently started taking Biotin. I have experienced irregular period. My OB RX progesterone 100 mg X 10 days and my last pill was yesterday. I am starting to spot again. I have never had this happen to me. This is my 3rd mirena iud because it sit too low in the uterus. Can you advise?