What does one do if they forget the number of days they did not fast in Ramadan?

The questioner : The questioner says: If I fasted some days of Ramadan, but I forgot whether I fasted those specific days or not, knowing that all I remember is that I had only one day left to make up, should I repeat the fasting of those days, or should I base my action on what I am certain of?

The Shaykh : If she is not certain that she had only one day left, then she does not fast more than one day. However, if she is certain that she had one day left, but she does not know whether she fasted it or not, it is obligatory for her to fast it, because the default is that the debt remains in her liability and she has not cleared her liability from it, so it is obligatory for her to fast it. This is different from the case where she is unsure whether she owes one day or two days of fasting, in which case she only fasts one day. As for the one who knows that she owes one day or more of fasting, but is unsure whether she fasted it or not, it is obligatory for her to fast it, because the default is that the debt remains.