Is my fast valid, or do I have to make it up, given that I was eating and drinking at the time of the Fajr Adhan out of ignorance?

What is considered for the obligation to abstain from ‫that which breaks the fast is the true dawn. So if the muezzin calls the ‫adhan before dawn, the fast is valid without any ‫problem. If it becomes clear that the ‫adhan is called at the ‫onset of dawn, the ‫ruling applies to ‫whoever consumed ‫a fast- ‫breaking ‫item ‫thinking that the ‫night ‫remained. The ‫majority of ‫scholars ‫hold that the fast is invalid and ‫qada' (making ‫up the ‫day) is ‫obligatory. Some ‫scholars ‫are of the ‫opinion that ‫qada' is not ‫obligatory, and ‫it is ‫permissible for the ‫questioner to ‫follow the ‫view that ‫qada' is not ‫obligatory.