Disspointed By the experience ... I would have expected better

I had called in 2 weeks ago because my insurance had become too expensive so i wanted to cancel,I was then told by outsurance that they are here for me and that i must not cancel as they would consider giving me a further R200 off. I then looked into my debits and worked out R1349 - R200 and expected to pay R1149 of which i had in my account only to find that i got debited R1499.99 and i did not have those funds available as I was given R200 off only to find that i have been assessed for the year and it went up by R400(if you take into account my discount) What a *******,Its like i was fooled to believing that i was discounted,I really thought you guys had me covered. i then call in and lady says i can give you R100 off .... How ridiculous.....and it will done for the next payment and then again on the 12/02 another debit goes out for R1499.99 and not enough funds again as i was still trying to sort my initial issue with you guys out ... Please can you call me so i can cancel.