Unable to get a paid up letter

Good day,

I would like to raise my frustration with this company their service is poor, I've been waiting for a paid up letter since last month May and when I call they keep on saying someone who assisted me did not do the request the one assisting me now will send the request I must wait again another week, I called again today and I was told the same that one did not request for the paid up letter story i must wait again I will get it before Friday.

I have been paying the account and they don't even update on the credit bureau it has affected my credit score, I don't understand why they don't want to issue a simple paid up letter document.

Regards, Thokozani