Mtn abnormal deduction

Please assist me to get my money back from mtn, they deduct my money 3 times in one month on May, their deduction for every month is 812,84, On the 25 may deduction.. 1629, 51 On the 26 may deduction.. 812,84

When I called them they say it's a future deduction meaning they won't deduct on the 25 of June. Surprisely today 29 June deduction of 812,84 I'm not happy at all I'm frustrated and angry. Why should mtn harass me and torture my emotions, I'm disturb really, please intervene