I have a few parrot drones myself - Bebop 1, 2, and Anafi. I purchased the Follow Me and Mission Plans a few years ago for each that has the feature available to it. The devices I installed the apps on with the "extra" purchased feathers (Follow Me and Mission Planner), most still work with it, but some don't. I ran into the same issues as you when I began using a newer device and attempted to reinstall the Follow Me and Mission Planner apps, could not connect to my Parrot account and reauthenticate them. In other words, the devices (2) that I have the Follow Me and Mission Planner apps installed on, are the only devices I can use those features with.
I don't believe Parrot maintains any of those apps anymore or the server they were attached to are no longer in service. I paid for both of those app features, but can no longer add them to any of my devices that don't already have them installed through the Free Flight Pro or Free Flight 6 App. Parrot is only concerned with their AI Anafi and USA Anafi (commercial drones). Consumer drones like the Bebops and Anafi's and their apps are no longer a concern of theirs it seems. Good luck to you. Hopefully someone else in this forms has advice on how to get those features for you drone.
