Vodacom contract/billing irregularities

I upgraded with Vodacom on 2020/11/17 with a package of R69 for 1gb data and R125.00 airtime;this is simi**** to an existing package that I have with them on another phone. I was given this package because I am a customer with them since they started doing business in SA. Together with the package I was given a 20 gb promo for a month. At the beginning of Jan 2021 I noticed that the package that I was given only consists of 250mb and not the 1 gb as agreed. After numerous calls I eventually had a discussion with a consultant and they agreed that for R79.00 per month I would get R125 airtime and 1gig of data per month. On receipt of my statement for Feb I notice that a new contract was created with a fee of R121.04 per month which is not consistent with what was agreed upon. To get through to Vodacom to discuss the matter is basically impossible;the calls keep on dropping and they do not return any calls. I do not see any alternative than to stop my debitorder/acb and take the matter from there;the service received is absolutely ridiculous.