Extremely Disappointing Discovery Insure Conduct

I am a holder of several Discovery policies, including a Discovery Insure motor warranty. This policy is structured so that when a client uses service providers within a network that is aligned to Discovery Insure, they get discounts on the overall amount spent. I serviced my vehicle on a partner in this network (i.e., Bosch Car Service City - Illovo) in August 2023 (1 Year from now) and I was eligible for a discount. I have since provided them with the invoices for the payments made at Bosch, and to date, I have been sent from pillar to post, requesting the same documents over and over again and this has not been resolved. All that was necessary, in terms of their stipulated processes, was for me to send them proof of payment indicating that I used their partner. I am generally a happy customer of Discovery, but the behaviour of Discovery Insure is, for lack of a worse word, appalling.