What is the ruling on the fast of one who drank, thinking it was the first adhan, after her clock was slow, or after her husband woke her up to a false alarm before the second adhan, and is there a make-up or sin upon her?

If someone drinks during or after the last Fajr adhan in an obligatory fast, they must make up that day. However, in a voluntary fast, making up the day is not required, but that day will not be counted as a fast due to the invalidity of the fast once dawn breaks. If someone eats or drinks, believing that dawn has not broken, and then it becomes clear that it had, their fast is invalid. If a man alerts his wife to drink water before Fajr, believing that dawn has not broken, and then it becomes clear that it had, there is no sin upon them in a voluntary fast, and no making up is required, but he should inform her afterwards.