Upgraded contract without my consent

Am really disappointed with Telkom that I have been with them for the past 5 years now so they then introduced the 80 - 80 gig plan I request it then few months after an upgrade boom was upgraded without my consent when I call to inquired I get lame excuses with no solutions but now am the one paying for a product I didn't approve to make matters worse Il have to pay for extra months I didn't consent for now this month again am being billed double Yoh shame am hurt n really disappointed with Telkom just wish this contract to fanish coz it's causing me nothing but stress with no solutions