Expired Credit Note

I wrote an email to Truworths' email: [Email Removed] on 22 February 2016 and have not received any response from them.<br> <br> My mother bought me a gift to the value of R399.00 in December 2014. I went to exchange it and issued a credit note to me.<br> <br> Not having had a chance to purchase another item using the credit note, and believing that same is valid for three years from date of issue (like all your other vouchers, and in terms of section 63(2) of the Consumer Protection Act) I went to Truworths, Bedford Center on Friday, 19 February 2016 to purchase an item.<br> <br> I was informed that it is no longer valid and expired within 3 months from date of issue. The cashier phoned the credit department at the Truworths Head office but they advised that there is nothing they can do and that the credit note had in fact expired.<br> <br> I would appreciate if they would issue me with a voucher to the value of R399.00 or furnish me with the cash, as performance from my side of has been effected, but not from their side. They are in possession of the R399.00 but I am not in possession of any goods. Therefore I believe that they have been unjustifiably enriched.