What Causes Heavy Bleeding With Clots And Abdominal Cramps?

hi doctor, my cousine is suffering from severe bleeding since past 2 weeks.she had had endometriasis and got treated for the same.recently she is suffering from heavy bleeding in the form of clots.doctor gave her progesterone tablets after taking which she got abdominal cramps severely.doctor suggested a DNC.we could not understand what the situation is.can u pls tell me what the problem actually is?how can it be treated? and immediate relief.