Delete a specific note in firebase in the Flutter app

I hooked up firebase and made the save data in it. But I can't delete a specific entry in firebase. I have a method , it removes all entries with the phoneNumber field, and I need to delete the entry with the phone number under which the user is authorized. In addition, the method listens when new notes are added with the phoneNumber field and deletes them automatically. deleteNoteByPhoneNumber() { [login to view URL]() .child('customers') .orderByChild('phoneNumber') .equalTo('+79644054946') .[login to view URL]((Event event) { [login to view URL]() .child('customers') .child([login to view URL]) .remove(); }, onError: (Object o) { final DatabaseError error = o; print('Error: ${[login to view URL]} ${[login to view URL]}'); }); Purpose: Write method for delete the entry in the database by phone number,