I accidentaly forgot that i was fasting and ate something does this brake my fast? I forgot my fast and ate. Does this invalidate the fast?

In the Name of Allah, Most Merciful and Compassionate

wa `alaykum as salam wa rahmatullah wa barakatuh

May Allah reward you for your question. The Prophet (Allah bless him and give him peace) said, "Whoever forgets that he is fasting and then eats or drinks, let him complete his fast, for verily, it was Allah who gave him to eat and drink" (Bukhari and Muslim). The scholars of the Shafi`i school deduced from this hadith that if one forgetfully does something that invalidates the fast, then one's fast is not thereby invalidated (cf. Minhaj al-Talibin). So if you eat or drink something during the day because you forgot that you were fasting, your fast is not invalidated. The moment you remember that you are fasting, however, you must spit out the food or drink that is still in your mouth. If you continue eating or drinking after remembering that you are fasting, your fast will be invalidated.

And Allah Most High knows best.

Hamza.