The Campfire friends list shows your friends from across all Niantic games associated with your Niantic account. There are a few reasons why your friends list in Campfire might seem incomplete:
You might have two separate Niantic accounts. If you’ve created a game account using a login method that’s not linked to your existing account, you will have created a brand new Niantic account with a separate friends list.
For example: If you play Ingress with your Facebook account and then you create a Pokémon GO account with Google login method, the Ingress and Pokémon GO accounts are not connected and will have separate friends lists. Campfire will only import your friends list over from one of the games. We’re not able to merge two Niantic accounts at this time.
Users must be at least 13 years old in order to use Campfire (in some jurisdictions, this age limit may be higher). Any friends that are under this age limit will not be able to use Campfire and therefore will appear on “Friends Not on Campfire” list.
Tip: You can view your friends list online at my.nianticlabs.com