Complain - Refund

On the 01 December 2017, i made a purchase of Zando shopping voucher vauled at R 300.00 for an amount of R 150.00. i waited pateintly and the voucher never came through, when i enquired on the 14 December 2017 for some weired reason it was not appearing on my Zando account they requested me to send through proof of payment of which i did and to date have not received any feedback neither my refund from them. Sent a follow up e-mail still no response and i decided to call them on the 07 March 2018 spoke to Natasha who said will log a request for my refund todate no refund has came through no feedback, i dont know what to do now.