A woman intended to fast on the day of Ashura and then her period came. Should she make up this day or not?
He says: the woman intended to fast on the day of Ashura, but her period came and she was not able to.
Should she make it up? The answer: she does not make it up, because this is a fast specified for a particular day. If you catch it, do it, otherwise there is nothing upon you.
But I hope that she will be rewarded, inshaAllah the Exalted, as long as she intended and was determined, but a valid excuse prevented her from fasting.