Is it obligatory to alert a Muslim who is eating or drinking forgetfully during the daytime in Ramadan, or is it that Allah has fed and given him drink, as stated in the Hadith?

Whoever sees a Muslim eating or drinking openly in the daytime during Ramadan must condemn it, even if the person has an excuse, such as being forgetful. This is to prevent the open display of breaking the fast. The forgetful person does not have to make up the fast, based on the Prophet's (peace be upon him) saying: "Whoever forgets while he is fasting and eats or drinks, let him complete his fast, for it was Allah who fed him and gave him drink." Similarly, a traveler should not openly display breaking his fast among residents, and disbelievers are prevented from displaying things that break the fast among Muslims.