Sayyiduna Abu Bakrah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) forbade bay' al-sarf (currency exchange) two months before his passing. (Allamah al-Haythami says:) I say: In the "Sahih" it is reported from him
that the Prophet (peace and blessings be upon him) forbade exchanging gold for gold, and no date is mentioned in it (as to how long before his passing he did so).
Al-Bazzar recorded it; its chain contains a narrator, Bahr bin Kaniz al-Saqqa', who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب البيوع / 6566