Discovery are useless

I purchased shoes at Sportsmans Warehouse on 16/07/2018 - OVER 2 MONTHS AGO - and I have been fighting with Discovery for my shoe booster payback ever since. They have said that their system reflects that I returned the shoes, which I didn't. I have sent them proof of purchase, pictures of the shoes, pictures of me wearing the shoes. I didn't return them, I don't know what else to say. I paid for the shoe booster as well as the shoes which means I ended up paying more for the shoes instead of getting them at a discount. The last I heard was on 14 Sept when I was contacted to say the issue had been escalated and Annestine who is dealing with it gave me her name and number and said it would be 3 to 5 working days. But I have heard nothing since, and the number I was given just rings and cuts off over and over. She mailed me from a "no reply" e-mail address but I have mailed Vitality over and over and no one comes back to me. Honestly over 2 months and NOTHING has been done and not to mention the time and energy I have wasted on this with absolutely ZERO feedback. Every time I purchase at Sportsman's Warehouse there is some problem.