"Nafi narrated to us from Ibn 'Umar, who said: 'The Messenger of Allah said: There is no transaction between the two parties until they separate, unless they have chosen to conclude the transaction."" (Sahih )
قَالَ رَسُولُ اللَّهِ ﷺ الْمُتَبَايِعَانِ لاَ بَيْعَ بَيْنَهُمَا حَتَّى يَتَفَرَّقَا إِلاَّ بَيْعَ الْخِيَارِ