Pathetic service ad billing system!!!!!

I've been with mweb for almost 4 years, however during that time my work had been paying for my wifi and unfortunately my contract expired 1st December. on the 5th December i called mweb myself to renew my contract with my banking details as i will be paying the wifi on my own and not my company. i chose the 100mg line for 849 however since my wifi was actived it was giving me speed of a 40mg line (what i used to be on) and every month i get billed for a 100mg line!!! im so flipping angry ive spoken to so many agents , sent so many speed test off, uploaded so many speed test on the app. I get told a technician can not be sent out as it up to vuma to decide if they can come out or not!!! i want to cancel my wifi and take it directly with vuma cause you guy are not going to compensate me at all or even try to help me !! R850 is not alittle money!!!!