Mjomba sees a suitcase in a shop window with a price label of Sh.5,000. he goes into the shop to buy the suitcase. He gives Sh.5,000 to the cashier but he is told that the wrong price tag had been attached and that the correct price is Sh.6,000. Mjomba insists that he bought the suitcase for Sh.5,000. Advise Mjomba