"The Messenger of Allah said;" Two traders have the choice as long as they have not separated, or until they reach a deal that suits both of th4em or that is satisfactory (to both)" (Using translation from Nasāʾī 4482)
قَالَ رَسُولُ اللهِ ﷺ «الْبَيِّعَانِ بِالْخِيَارِ مَا لَمْ يَتَفَرَّقَا أَوْ يَأْخُذْ أَحَدُهُمَا مَا رَضِيَ مِنْ صَاحِبِهِ وَمَا هَوِيَ»