She has not yet made up the fasts that she missed
Question

I have not yet made up the fasts that I missed in Ramadaan when I had my period, and I do not know how many days I missed. What should I do?
Praise be to Allah.You have to try hard to fast the number of days which you think you most likely missed, and ask Allah to give you help and strength. Allah says:
“No person shall have a burden laid on him greater than he can bear.” [al-Baqarah 2:233]
 Try your best to be on the safe side and fast the number of days you think is most likely that you missed. You also have to repent to Allah, and Allah is the Source of strength.