The Messenger of Allah ﷺ as saying: Each one of the two parties in a business has an option (to annul it) against the other party so long as they have not separated, except in a conditional bargain. (Using translation from Abū Dāʾūd 3454)
أَنَّ رَسُولَ اللهِ ﷺ قَالَ «الْمُتَبَايِعَانِ كُلُّ وَاحِدٍ مِنْهُمَا بِالْخِيَارِ عَلَى صَاحِبِهِ مَا لَمْ يَتَفَرَّقَا إِلَّا بَيْعَ الْخِيَارِ»