Can no one read !?!?!?

I have queried missing cash backs for qualifying Vitality Healthy Care products since the 9th of November. I have sent them 6 invoices/slips and have even highlighted the products in question. They simply insist that feedback on a single item is sufficient to close the call. They have processed a single manual cash back reward for a single item. They simply refuse to read, or perhaps they are just purely ***********. Shocking how they deem to be the level of service they pride themselves with.