The Messenger of Allah ﷺ said, "None of you should sell over the sale of another, nor should a town-dweller sell on behalf of a desert-dweller. Do not inflate prices artificially, and do not intercept goods before they reach the market."
حدثنا محمد بن إدريس أخبرنا مالك عن أبي الزناد عن الأعرج
أن رسول الله ﷺ قال لا يبع بعضكم على بيع بعض ولا يبع حاضر لباد ولا تناجشوا ولا تلقوا السلع
Its isnad is sahih, it has occurred many times before, see 4722, and it is found in Bukhari 3/90, Muslim in Nikah no. 49, and Buyu 7, 11, Abu Dawud 436, Tirmidhi 1292, Nasai in Buyu chapter 20, and Ibn Majah 2171.8918m - He said, "Delaying payment by a wealthy person is injustice, and if one of you has his debt transferred to a solvent person, let him accept the transfer." Sahih (8918m). Its isnad is sahih, it has already been mentioned at 8882, and it was reported by Bukhari 2/132, Muslim in Musaqah 23, Abu Dawud in Buyu chapter 10, Tirmidhi 1308, and Nasai 7/317.