If the blood of the postpartum lasted for a long time; one or two months, and the woman did what is done with…

Answer

In the name of Allah, if she is of regular menstruation (like the pregnancy and birth), she can know her days of menses. In case she is not of regular menstruation, if she can recognize it, she will go ahead, but if she could not recognize it as the blood comes out in one state, she can act on Istihadha ten days in a month and three days in another. Allah knows best.