OVERDUE account- not happy, need proper response

Since 2011 I have complained to Vodacom in-store, with managers, both in Nelspruit & Cape Town, on hello peter - this may be my 3rd time and via email and numerous calls. <br> I refer to my last contract with Vodacom. When i upgraded my contract I SPECIFICALLY asked for same monthly charge for subscription as before- as I've strict budget as a single parent- was currently in legal maintenance court battle. <br> For the 1-2mths total was same amount but then jumped to almost TRIPLE the bill thereafter! I went in to enquire why & they merely stated it was my use. Fair enough i was using the phone HOWEVER at no time did the sales person state how the call or sms's would be sooooo much more... <br> The manager then said obviously the sales person didnt explain contract package to me in detail &<br> it wasnt the correct package for my usage. <br> <br> Eventually after desperation I bought pay-as-you-go number & didnt use the contract number for months prior to contract expiring. My current monthly bill is less than R100 pm. I am happy to make a payment arrangement for amount outstanding until last day of the contract- I'm not prepared to pay for the interest, due to inconvenience caused to myself!