Debonairs Pizza Call Centre/Customer service never comes back to you

Received a Birtday Voucher. It kept failing to load. I contact Debonairs via WhatsApp and the bot said that it has forward my problem and someone would contact me. I sent 25 emails and phoned 3 times. 2 calls was put down. The 3rd one Promise promised to phone me back by the end of the day. It's days later. In fact it's more than a month struggling to get hold of them - the broken voucher already expired meaning it's been more than a month I had Pizza.

It looks like there is no one at their head office or they are dancing and they do not want me to buy their Pizza. Maybe they will close business anyway soon!!