Change my phone???

Videotron is telling me I have to change my phone to "avoid any unpleasant surprises" Thing is, my phone, an LG6, works fine and I don't WANT to change it!!! I'm a senior and can't take any hassle.  I use my phone for very little - just ordinary phone calls, mostly local, and don't travel. So will my phone still work? What "unpleasant surprises" are they threatening me with?  Do I HAVE to change my phone to stay with Videotron?  Thanks for your advice!