Musannaf Ibn Abi Shayba 13:2605

Abu Bakr narrated to us, he said: Ibn ‘Uyaynah narrated to us, from ‘Abdullah ibn Dinar, from Ibn ‘Umar, he said: The Messenger of Allah (ﷺ) said: "The two parties to a transaction have the option (to rescind) as long as they have not separated, unless it is a transaction of option."