It is narrated from Sayyiduna Abu Sa'id (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) was asked about a fasting person who ate and drank out of forgetfulness. He (peace and blessings be upon him) did not order him to make it up and said: "That is simply food that Allah fed him."
Imam al-Tabarani (may Allah have mercy on him) said: "This hadith is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) only with this chain, and Muhammad bin Ubaydullah (may Allah have mercy on him) is alone in narrating it."
Hadith Referenceالمعجم الأوسط / باب الميم / 6365
Hadith Gradingمحدثین:إسناده ضعيف لضعف محمد بن عبيد الله العرزمي
Hadith Takhrij«قال بدر الدين العيني: هو ضعيف يعني الفزاري «عمدة القاري شرح صحيح البخاري، ج 11، ص 17»» «قال الهيثمي: فيه محمد بن عبيد الله العرزمي وهو ضعيف «مجمع الزوائد ومنبع الفوائد، ج 3، ص 157»» «أخرجه الدارقطني فى «سننه» برقم: 2240»