'Flutter run' in terminal cannot connect to VM Service, connection refused

[Annelein]

If I run 'Flutter run' in my terminal after a while it says:

Connecting to the VM Service is taking longer than expected...
Still attempting to connect to the VM Service...

Exception attempting to connect to the VM Service: SocketException: OS Error: Connection refused, errno = 61, address = 127.0.0.1, port = 50940
This was attempt #50. Will retry in 0:00:01.600000

But if I run it in X Code it works..

I have no clue what I am doing wrong,
flutter doctor -v doesn't give any exceptions (see screenshot)
I also attached a screenshot of flutter run --verbose and the pubspec.yaml

Apparently it is not a Flutter issue but a Firebase issue that's why I'm asking here..

Anyone that could help me out?