Experiencing issues with mobile app Build (version, compatibility) Gradle Capacitor

Hi everybody,
I’m facing troubles emulating and building my mobile app builds since the last 2 days.
I’m working on adding Firebase Cloud Messaging on my mobile App (Android + iOS)

In order to do that I needed to add:
https://capacitorjs.com/docs/apis/push-notifications
https://capacitorjs.com/docs/guides/push-notifications-firebase

Then setting up files (google-services.json + GoogleService-Info.plist), installing them and did some modifications on AppDelegate.swift and AndroidManifest

The next steps should be adding some JS code to launch and detect Push Notifications autorisation + get FCM TOKEN so I can register it associated to my user_id… bref…

Since I installed additionnal capacitor package, it’s a nightmare…
I’m fighting against compatibilty problems bertween gradle version / capacitor version / capacitor plugins version… I did hundred of tests, upgrade, downgrade, rebuild, settings…

I’m not able anymore to launch any build and go futher in my app feature devlopment.
I need to find a solution… and help.

Many many thanks

(note: I experienced the same issues trying to build a brand new empty project with capacitor)

Did you manage to solve this problem? I’m in the same situation here.