Hi Doc, One Of My Friend Got Early Abortion In

Hi doc, one of my friend got early abortion in with in 2 weeks of pregnancy with misoprostone. Then a gynecologist declared that she should be done with d&c as few retailed products are present. After d&c she got blèeding for 4 days and stoped. After 1 month 7 days also she did not get her peroid. There were no RC visible in ultra scan also. What is the reason. What can be done?