Sim Contract can’t be cancelled and it’s never been used

I’ve requested mtn several times to cancel the contract that they gave me in November I never used sim because no one told me it’s only for home router I dont have home router and never used the sim yet they still kept the line on and debited my account this month.when I call mtn the agent keep taking me to different people I want mtn to cancel the contract if they continue they’ll see to finish who will pay the account. Some agents just wanna make commissions at our expense I’m not paying for that stupid sim my number is ***. I’ve been calling they gave me runaround until the 10 days passed then they advised I can only cancel within 10 days. People pushing sales and commissions with our moneys