MTN cannot expain charges dodging for 3-Months now

I upgraded my ****le to a new wifi offering when i got a call from MTN Direct. I was so impressed with the offer I took an additional wifi ****le with exactly the same date etc. In the voice contracting there were no mention of additional charges or a possibility thereof. Since January a charge of R147 odd rand has been appearing on the billing of the two ****les, when calling the 808 number and holding on forever I get told with an attitude that I have purchased additional data bundles on the wifi ****les??!! When questioning the consultant how this is \transaction"can be done without me knowing nor approving anything the consultant had no explanation except that she can escalate the matter to their technical division and promised to give feedback. that was in Feb. March the mysterious charges appeared yet again overcharging me with 300 a month consistently I phoned 808 again where I insisted on speaking to a manager. Thembinkosi Khumalo was the manager on duty and promised me feedback verbally and via E-Mail once he has a resolution to the matter"