Vitality trying to wiggle out of cash back responsibility

This is not news to most people: Client service for Discovery Vitality is non existent. We have still not received Vitality cash back from July 2020 that was supposed to be paid out on 15/08/2020. Initial mail sent in second halve of August was rep**** that cash back was delayed and would only be paid out in September 2020. Second mail after non payment in September was rep**** that as we cancelled our membership effective 31/08/2020 that no payment will be made. Makes sense? As I was still a member in July and August I should at the very least receive my cash back for July.