R1600 in pecu**** data charges, no warning.

On 15 August 2015 my cellphone was ****** and my sim card black listed, on 17 August 2015 I did a sim swop. Some time during the theft my data bundle allegedly run out. Normally I receive smses from vodacom reminding it has run out and I load a new bundle. On this occasion I did not receive any notification and proceeded to use data for the remainder of the month out of bundle rates. Normally my bill would be R1000 this month it was R2600, surely vodacom should have notified me long before the bill even reached a third of that. I distinctly remember blocking may account at R1500 but the call centre advise me otherwise, convenient. Notwithstanding this terrible service I also noticed my data billing is very strange, I apparently used 3 times more that month than I normally would and it is always at midnight except on 3 occasions.On 28 September I logged a complaint and was told it would be investigated, it is 19 October and despite following up with them last week I have received no feedback on my account. I have now requested to cancel- I am due an upgrade in 1 month but I would rather pay R2000 penalty to cancel than stay with a business who treats a longstanding customer this way