Cancellation nightmare

I had 4 lines with vodacom, I had upgraded two lines and I wanted to cancel the other two, however I’ve since called retentions and logged cancellation on my lines but I was so surprised when I got billed for the 2 lines I have requested cancellation for, called in to query I was told that there’s no record of me calling in for that cancellation request I have then requested call recordings for that particular day and that was last week even now I haven’t had any response. Now I have to pay for something that isn’t part of my plans all along, these is very inconveniencing and disappointing coming from vodacom. I need this issue resolved asap