I exchanged a garment for another one at the same price and Truworths staff at Ballito Junction were unable to apply the discount to the exchanged item

I exchanged a garment for another one at the same price and Truworths staff at Ballito Junction were unable to apply the discount to the exchanged item. They provided feeble excuses and then **** to me that the discount will be processed by Head Office. To date the discount has not been processed and Truworths is ignoring my e-mails.