Flutter Null Safety Migration says `Package doesn't exist`
Try flutter pub outdated --mode=null-safety, should display the the migration state of your package’s dependencies.
Can't see anything obvious here, the command is just a lookup you can still check all dependencies on pub.dev manual when all the packages support null safety and the other commands are working you should be fine.
I only have one idea the beta channel should be fine in most cases, but switch to stable if nothing works
flutter channel stablemake sure you run flutter upgrade
First run:
dart pub outdated --mode=null-safetyand to upgrade your packages to null-safe variant, run:
dart pub upgrade --null-safety