Charges of R20 for every email and phone call!

I sent a mail to customer services, but I doubt I will get a response. My account has always been managed well, at times in a credit. Recent times hardly purchasing anything, yet my account always has an outstanding. I must have paid less R70 last month and received a call to pay by the next day. I paid R200 yesterday. This morning someone calls me just after 7am to say I have not paid the R70. I was not too happy being disturbed at that time. Then I received a harsh toned message to say pay today, after I told the consultant that I paid already. I just checked my account online and am absolutely shocked. You are charging me R20 for every email and phone call! What is Account Benefits?? A charge of R31.64 monthly? Please close my account and let me know the outstanding and what it is for?