********* behavior by Vodacom !!!

I renewed 3 cellphone contracts over the last couple of months. Vodacom "loaded discount promotions" on all 3 lines. The renewals were done over a couple of months with the first one was done in September. I called them numerous times and every time I'm being told that the bill will correspond with the agreed cost from next month. Needless to say, it's December and the bill still doesn't correspond and I've been overcharged since September. Don't even bother asking for recordings of the calls. You will NEVER receive them !!!