billed Unnecessarly

i have contact with Telkom for two phones. one with only data and the other with data & minutes. i specified that on both numbers after using whatever that give they must blocked the both numbers from any charges, meaning no extra charges. to my surprise i was billed R494 on the 26 of Jan instead of R299. i called on the same day & was told that i had content services & that the name of the company & contact details did not appear on the system & the person promised to cancel the subscription, which i don't understand why it got there in the first place. cause to my understanding content services takes airtime is loaded on your. so Telkom is giving me minutes instead of airtime. so how come are they billing me for content services for which they were suppose to block any other apart from the minutes they give, & to my understanding content services are suppose to take airtime that i have on my phone, not my service provider. they still took that R494 even this month and still cant explain what it is for & they are telling me to go to the person who assisted me at the store the first time i opened the contract cause that's the person that made a mistake who nomore works there.