"Whoever eats out of forgetfulness while fasting, let him complete his fast, for it is Allah Who has fed him and given him to drink." (Using translation from Ibn Mājah 1673)
أَنَّ رَسُولَ اللهِ ﷺ قَالَ إِذَا أَكَلَ أَحَدُكُمْ أَوْ شَرِبَ نَاسِيًا وَهُوَ صَائِمٌ فَلْيُتِمَّ صَوْمَهُ فَإِنَّمَا أَطْعَمَهُ اللهُ وَسَقَاهُ