Vouchers not working on Woolworths app

I use the Ww credit card and get two vouchers for coffee every month. This month they did not open so I could get the coffees. I reported it twice to the Lonehill manager and he couldn't get them to work. He promised to phone head office - not sure whether he did. I have reported it twice on the Ww website - still no response to either report. I have deleted the app and reloaded it. I have cleared the cache. It still doesn't work and nobody at Ww seems interested.