Is it permissible to sell gold to a store, then buy other gold from the same store after receiving the payment, and is it valid for the seller to stipulate that one must buy from him?

There is no harm in selling gold to a shop and receiving its value, then purchasing the desired gold from the same shop for the same value, based on the hadith: "Gold for gold, and silver for silver...like for like, equal for equal, hand to hand. But if these types differ, then sell as you wish, provided it is hand to hand." However, the shop owner's condition that one must buy from him in exchange for him buying the gold is impermissible, because it is a corrupt condition that invalidates the sale.