Hello @SunsetRunner and welcome to the Help forum. I apologize if I am misreading your post. It sounds like you had your previous phone set up as a device using MobileTrack. Since you got a new phone, you need to set up that phone to use MobileTrack. Tap on your profile icon, then + Set Up a Device, then choose MobileTrack and continue.
Laurie | Maryland
Sense 2, Luxe, Aria 2 | iOS | Mac OS
Take a look at the Fitbit help site for further assistance and information.