The Messenger of Allah ﷺ said, "It is not lawful for a believer to shun his brother for more than three days."
أن رسول الله ﷺ قال: لا يحل للمؤمن أن يهجر أخاه فوق ثلاثة أيام.
Muslim narrated it in Birr and Silah (2561), from Muhammad bin Rafi, who said, Muhammad bin Abu Fudayk narrated to us, Dahhak, who is Ibn Uthman, informed us, from Nafi, from Abdullah bin Umar, and he related it.