I followed all the steps on the docs to use Firebase Crash Reporting in my Android app (I use Android Studio and everything is up-to-date).
I used their own code to t
Crash reporting was not working for me too after correctly setting it up in my App. To fix this I visited my developer console, API Manager, and enabled the "Mobile Crash and Performance Reporting API". To find out exactly where you need to do this follow the steps on this page.
If you follow the steps in the link above, the logcat that has the text "E/FirebaseCrashSenderServiceImpl: Error sending crash report" gives you a URL to where you must go in the console to enable crash reporting.