Bad customer service

So disappointed and embarrassed by the store manager.On 30 March i bought some items at exact including a hand bag that was on promotion it was 299'90 and u save 100 was suppose to pay 199.90,when I arrived home i check the receipts only to found out that the bag was not discounted with 100 it the Easter holidays we went away the same day when come back Tuesday,Wednesday i went to exact to show them that they didn't give me the discount thinking they will fix the mistake they told me was suppose to come the same day now the promotion is finished the is nothing they can do the a only going to refund me ,or i take the bag with that money or they a going to refund me n I loved the bag but I can't pay 299.90o bought the bag when it was on promotion ,they refunded me mind you was using the bag they gave me a plastic bag to put my things in it so disappointed,I think I deserve that bag with discount i bought it when it was on promotion.