Cancelation bill

Still haven't get help with my bill for something i never used (home wifi) that i did canceled and they want to keep on paying cancelation fee for a wrong home wifi they sent to me and they even checked if i used it or not and the mondo they said they sent email to them about my report of the wifi is never been used now today the mondo says i have to pay cancelation fee for something i never used and i have been paying for 4months.i am so sick of this companies they want myoney for something they sent it will knowing is wrong is not my fault yo be honest .