Phone and talk with a Telus rep - they should be able to guide you on what exactly you should do.
In the meantime, here is how you can utilize 'Call Trace' with Telus.
When we were still with them, they changed our number for free, because it was one digit off for a car rental place in Calgary and we couldn't get people to stop calling us inquiring about rentals. So they switched it for us. I'm not sure if they'd charge you to change it or not, but even if they do, it might be money well spent. Then just be careful about who gets to have that number, I guess.