Overcharged by 43% each month on my contract without explanation or reply

Vodacom has been charging me R2300 on a contract that cost R1600. I signed up for the R1600 contract - was told that is what Ill pay each month and then got charged R2300. I also dont receive bills (even though Ive aksed for these multiple times) and had to discover these figures on my bank statements while doing tax recons. Now I have tried several avenues to find out why and to correct it but my requests have been ignored for months - I phoned call centres, sent sms', tried your social media page and contacted Linkedin contacts. Today I spoke to a call centre agent who tried to sell me an upgrade and she finally corrected it going forward and explained that I get nothing extra for the nearly R1000 more Ive been charged per month - VODACOM JUST DECIDED TO TAKE THAT AMOUNT INSTEAD OF THE R1600. It is amazing how you are able to get in touch when you are selling something but not when I have a problem...

I am highly disappointed that this is the way Vodacom decides to trade. I need an immediate refund of my money that you...well, I guess stole is the best way to describe this. Ombudsman and more Social Media will be my next step... or as far as I need to take this. Consider me a thorn in your side until this is resolved