Hi. I'm 42 Years Old. After The Birth Of My

Hi. I'm 42 years old. After the birth of my second child, I went on the mirena IUD for birth control and to control my periods. Over the past ten or so years I have had two iud's inserted, with great results. About five months before I was going yo have the second one replaced I started spotting a lot. In February, I had a new a Mirena inserted and have been spotting for 8 months. Sometimes more than spotting. For the past month or more it has been period like. What is causing this? The first IUDs were good. What should I do?