Al-Sha'bi (may Allah have mercy on him) narrates from Utbah bin Farqad (may Allah be pleased with him): I bought ten acres of the land of the Sawad on the bank of the Euphrates. When it was mentioned before Sayyiduna Umar (may Allah be pleased with him), he asked: Did you buy it from those landowners? I said: Yes. He said: Come to me. I went to him, and he said (to them): Did you sell him anything? They said: No. He said: Take back your money from where you placed it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18411