why i am not able to use FirebaseDatabase in android studio

Question

my problem is when i want to use FirebaseDatabase ; android studio Cannot resolve symbol 'DatabaseReference'

user_14841644 · Answer

you can try clean Project (Build-> Clean Project) or Invalidate Caches(File->Invalidate Caches -> Invalidate and Restart)

user_13720647 · Answer

Please check if you have these dependencies in your build.gradle (Module:app) file.

 implementation 'com.google.firebase:firebase-database:20.0.5'
 implementation platform('com.google.firebase:firebase-bom:29.2.1')

For further guide on how to setup firebase properly please visit this.