Can't Cancel Account

I have been trying for 8 months now to cancel my account. I've sent over a 150 emails and attached the form they told me to send as well as proof of identification. I've tried using their online cancellation form m and I've even phoning them on multiple occasions. The employees I've spoken to have confirmed they have received my documentation but every month I get another bill. I'm assuming they are not cancelling phone lines so they can ****** money from people who were unwillingly forced to have a phone line with them and no longer need them. These shady business practices are typical of a ******* and underhanded business.