not transparent and pathetic service from the call

I got a call from one of the call centre agents just before I got paid for June to make payment arrangements and Faith made an arrangement that I can pay R900 on all my 4 accounts Everything was agreed upon, however on the 25th June 2015 a total of R1774.76 was debited on my account, I then call the call centre on 2 July 2016 to get this sorted out from my cellphone and I'm made to hold on the line for over 7minutes and just as she tells me the feedback the call gets cut, me being the client and had made this agent aware that I was on a cellphone, I expected a call back for her to tell me the resolution but no. I had to call again and apparently I cannot be transferred to the same agent, and I had to relay my whole story and mind you I'm on a cellphone. So the last agent I spoke to advised that the reason they debited more was because I'm in arrears, point taken but what was the whole point of the arrangement? So because no one can assist, here's my resolution, I will reverse the debit orders from the bank (even though this will affect my credit profile) and go and pay in cash what the initial arrangement was