ʿAbdullāh ibn Dīnār said: I heard ʿAbdullāh ibn ʿUmar (رضي الله عنهما) say: ‘I heard the Prophet (ﷺ) say: “The two parties to a sale have the right of cancellation (khiyār al-majlis) so long as they have not parted, or unless it is a stipulated option sale (bayʿ khiyār).”‘ Reference: Musnad Aḥmad 7