وَعَنْ اِبْنِ مَسْعُودٍ رضى الله عنه
قَالَ: سَمِعْتُ رَسُولَ اَللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ: «إِذَا اِخْتَلَفَ اَلْمُتَبَايِعَانِ لَيْسَ بَيْنَهُمَا بَيِّنَةٌ، فَالْقَوْلُ مَا يَقُولُ رَبُّ اَلسِّلْعَةِ أَوْ يَتَتَارَكَانِ»
I heard the Messenger of Allah (sallallahu alayhi wa sallam) saying, “When two people who are arranging a business transaction disagree and there is no proof to arbitrate between them, the seller’s word is final, or they may break the deal.”.
Bulugh al-Maram 892, Book 7, Business Transactions, Hadith 3. 1 min read