Why couldn’t you keep the old “untrackable” one?
FRmail as necessary ;)
We had “old” phones (2000) and got newer ones, which we didn’t really like but stuck with for a few years. We finally got sick of the new phones and tried to go back, some time around 2006 or so. The phone company refused for the stated reason, and gave us new ones. By that time “all” phones were trackable, but our fossil ones weren’t. They also claimed that the phones were incompatible with the new service, 3G or whatever it was.