Abu Salamah (may Allah have mercy on him) said that Sayyiduna Abd al-Rahman bin Awf (may Allah be pleased with him) bought a slave girl from Sayyiduna Asim bin Adi (may Allah be pleased with him). He was told that she had a husband, so Sayyiduna Abd al-Rahman bin Awf (may Allah be pleased with him) returned her.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10750