Oh geez. That's surprising and disappointing. Yeah you've put in enough effort, it might be time to warn them that you're going to file a complaint with the CRTC. Sorry man. McDVOICE
There is not much more that you can do right now, except to keep following up until you get your due but at least by documenting it you strengthen your case. Don't forget social media - these companies don't like complaints aired on social media for all to see so they will generally address it.