Unhappy with the call centre

I am unhappy with the service delivery from DStv call centre. I made a payment with incorrect reference number, called in the call centre, emailed the proof of payment on the 8 May and I was assured that payment has been allocated accordingly, boom today could not connect to any channel on due to non-payment, when I called in again I was told the services were only preset and that u should send in a letter for the payment to be allocated, did that now they are waiting for the department dealing with proof of payment to allocated, they should just told me to send in a letter at first.