Vodacom DataBundle price issue still not solved

Hello sir,

My data contract was 2 GB +2 GB will expire on January 2019 cell number( ********** 502). so recently I called customer care to cancel my data contract then they asked me why do you cancel data contract. i said Cell C is giving 10GB +10GB day and Night data only per R200. then Vodacom customer said to me they give same data 10GB+10GB only per R149. so I accepted it. but now they sent me invoice with R212.00 . now i wanted to cancel contract but they are telling they charge all 24 months contract fees. I am not happy with their deals. please help assist me. they are changing words from minute to minute .

kind regards Naga