Disgruntled Customer

I have contacted Cell C in June to change my debit order date from the 25th to the 1st, my account was not debited and I did a eft on the 4th of August and I have been calling them since the 1st of August and to date they keep saying they have not received the payment even though I have sent POP more than once. As a loyal customer for over 10 years I am utterly disgusted with this pathetic service