Getting billed for service I don’t have

I got a letter from Telus saying they are no longer providing land lines in our area.  I tried multiple times to switch to the voip they were offering but after a few unsuccessful and frustrating attempts I switch to Shaw. This was August 5

I got a call from the retention team asking why I switched and explained why.  The number was ported to Shaw however I continue to be billed from Telus. After multiple calls and chats with Telus I am still getting the run around and continue to be billed.  The latest rep Patrick tells me I need to talk to the retention team as the account is still active.  I explained I already talked to the retention team back in August. Today I received another bill for next month and go through the same run around again.  As we speak I’m been transferred to a different department again and been on hold for 55 mins.

I called again today and was transferred to the loyalty team who then transferred me to a different department where i was on hold for another 40 mins

Long story short I should not be billed from August 5 until now but continue to go around in circles.