I oversleept and missed the suhoor time, but thought that my mother told me its 2:45 my brain took it that way and got up just ate something small then my nonfasting brother this day because he was sick last day told me its in fact 3:45 and suhoor has 15 mins that it has ended and i didnt know what to do i am keeping the fast, is the fast valid ?
Scholars differ on this. To my knowledge eating by mistake after the suhoor time will not break your fast, as long as you made the intention (niyyah) to fast. So you can continue fasting. However, just to be safe, you can make up this day.
Allah knows best.
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