I was building my first application for my graduation project, using android studio based on java, and connected my project to firebase so I can save the registration data in firebase, then faced a problem regarding "google-services.json" file that I must download into my project, which I did along with some other lines in this directory "Project-level build.gradle (/build.gradle):", following the instructions on Firebase console, after I finished all these steps I synced the project. that's when my app won't run any more and show me this error every time I run it:
Please help.
The problem was in the Firebase side, if you changed the name in the android studio nothing will happen, because I did. But what worked for me is to create a new app in Firebase console with the same name from the error message that kept appearing every time I tried to run my app: "No matching client found for package name "com.example.labbookingsystem", which in my case will be "com.example.labbookingsystem".
Credit for the solution: https://www.youtube.com/watch?v=0D0RGXSAhL0
Note: it is in 480p but it is worth it.