paid up letter

I was behind with my payments on a contract phone that I'm using and then my contract was written off and then I paid an amount of R13 335.49 on the 14 march 2018 settling the amount I was owing. what I was told that after paying the settlement amount I would then have to wait for a period of 72 hours to get the letter , a case was escalated by one of the argents by the name of Engel Mthembu ..I have not received the letter even today , question is how is it that thy rush you to pay your account and delay to send you a paid up letter after the turn around time they mentioned to me as a customer ,they are not taking my case as an urgent they are not helpful at all one of the consultants hung up on me after holding for 35 minutes ( her name was Gugulethu Mbatha ) and finally I spoke to one of the team leaders which was Paul , still there was no joy as Iv been told the same story of they will escalate my case.. I am in a process to get a loan to buy a house but this letter is putting my life on hold because of people who are in customer services , but cant even service us as customers , since they couldn't put me through to their managers I would like hello peter to help me in this regard