Vodacom lie and *****

So I phoned vodacom made arrangements to settle my account that was in arrears. We made the arrangements and I paid after that the staff apparently don't see the arrangement then I request for a supervisor to phone me, later the day Supervisor Nomfondo phones me and says she can see the arrangement I I need to pay R5000 then I'm done so I payed the last installment and now for 4 days she is ignoring me and I need a letter to state I hold up my side of the agreement. When I ask for the recording of our phone calls the refuse to give it because they lie to clients and try to cover them selfs I want a manager to phone me regarding this matter