Disgusting Service from Debonairs

Absolutely disgusting service from Celtis Ridge Debonairs. I tried to place an order online as I had a Wi-Code voucher for R200. When trying to pay for the difference the app said "ordering issue". I tried to go back into the App to order but alas i had now lost my Wi-Code voucher as you can only enter it once. Noticing that the difference had been deducted from my Account I tried to call the store but with no success. I then got in my car and drove to the store and was met by a rude and disinterested manager. On explaining what had happened he told me he didn't understand what my problem was and what I was saying. I then showed him the screen shot of the ordering issue and he once again said to me that he doesn't know what my issue is and that I can place an order now and will not get the voucher back. I was livid and left and went to another pizza place. Is this the service that Debonairs offers - take the R200 voucher and doesn't care that the customer actually didn't get anything. When trying to write a complaint on their system I got a notification when trying to submit - Sorry there was issue sending your mail. It is not the 1st time I have had terrible service from this Group of Take-Aways. Last time it was Fish Aways where they gave me the wrong item on my burger and i had ZERO response from them when sending a mail. DISGUSTING!!