Sayyidah Umm Ismah al-Awsiyyah (may Allah be pleased with her) narrates that the Messenger of Allah (peace and blessings be upon him) said: "There is no Muslim who commits a sin but the angel appointed to count his sins waits for three hours; then if he seeks forgiveness from Allah Almighty for that sin at any moment during those hours, he will not be held to account for that sin on the Day of Resurrection."
This hadith is narrated from Sayyidah Umm Ismah (may Allah be pleased with her) only with this chain, and Abu al-Mughirah (may Allah have mercy on him) is alone in narrating it.
Hadith Referenceالمعجم الأوسط / باب الألف / 17
Hadith Gradingمحدثین:إسناده ضعيف جدًّا، فيه أبو مهدي سعيد بن سنان متروك
Hadith Takhrij«قال الهيثمي: وفيه أبو مهدي سعيد بن سنان وهو متروك «مجمع الزوائد ومنبع الفوائد، ج 10، ص 208»» «أخرجه الحاكم فى «المستدرك» برقم: 7770»