MTN

I have been asking for cancelation of the router since last year October due to network problems after they tell me to call their call center, which I did, but they transferred me back to the where I bought. Then they told me I was using wrong address to my surprise I was using that router for more than 4yrs. After few months months of trying they call me to change the router I did not knowing I fall on a trap, they sent me new router not knowing they will charge me both, actually January after the delivery of a new router it only works for 2hrs, I phone them no help they deduct R700 then R2240 and I send emails tons of emails lastly they are on it today they deducted again and I have sent back the router back las month. Please help as I imotianally stress