Don’t use FNB credit card division . They take what’s not due to them and refuse to give it back

Extremely bad service. Waiting for my 3 weeks later and no one can tell me what’s happening. After more than 10 calls and escalations nothing is happening. I want my refund . Don’t care about anything else . Just give me what’s due to me . I have sent enough proofs and mails . I won’t go way until my money is refunded.