Waiting for Paid Up Letter

I WANT MY PAID UP LETTER I requested a settlement letter and a discount on the amount I owe on my Capitec account which I received and I was told by one of the call centre agents that once I send the proof of payment he will forward me the paid up letter. When I forwarded the proof of payment the call centre said I must wait 21 days before I can get my paid up letter. This is unacceptable I have paid up my account and need my letter as soon as possible . I am very unhappy with services and that after more than 20 attempts in phone calls, and several emails I still have not received it. I paid my account in November 2018 and until now in January 2019 I have not received anything. I have all the emails they send me.