Post pregnancy unexplained bleeding for 7 months

Just like the title says I’ve been bleeding nonstop for 7 months. I’ve went to my dr she’s tried one pill I forgot the name to see if it’d stop it. It was 10 days I had to take them. Didn’t work. Then this last appointment she gave me a second kind of birth control ( I have the Mirena) a pill I’ve been taking a month containing estrogen thinking my levels were low and guaranteed to stop it. It hasn’t. I previously had the nexplanon and for the same reason (bleeding) I had it removed.and got the Liletta iud. Obviously Im going back to my ob unsure of what the next steps are but does anyone have any explanation? She’s at a loss as to why it hasn’t stopped. As am I. When asked when my last cycle was idek and have to say I’ve been bleeding basically since I had my 4th daughter(csection). Thanks for reading