telephone problems ( that are not videotrons fault)

I have 3 vtech wireless cordless phones on my system with no problem , I needed an extra phone for my computer desk . I bought a vteck phone old style cord attached to base , base plugs into the wall . It took me a year to realize that this phone cannot connect to locals or extensions. I am a caregiver and contact the Quebec CLSC's often All my other phones are ok but this phone gets extension or locals not in service at this time . Has anyone ever heard of this problem with older style phones ? 

Bob F.   a caregiver in Montreal