title: Firebase - email address is already in use by another account
body: <p>When I try to login in my app with fire base authentication it shows email address is already in use by another account.I can't figure out what is the problem.   </p>
  
  <pre><code>public class LoginActivity extends AppCompatActivity {
  
  private EditText login_email, login_password;
  private Button login_button;
  private FirebaseAuth firebaseAuth;
  
  private ProgressDialog progressDialog;
  
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_login);
  
      login_button = (Button) findViewById(R.id.btnLogin);
      login_email = (EditText) findViewById(R.id.login_email);
      login_password = (EditText) findViewById(R.id.login_password);
  
      firebaseAuth = FirebaseAuth.getInstance();
  }
  
  
  public void onClickLoginButton(View view) {
  
      progressDialog = ProgressDialog.show(LoginActivity.this, " Please Wait...", "its processing", true);
  
      firebaseAuth.createUserWithEmailAndPassword(login_email.getText().toString(), login_password.getText().toString())
              .addOnCompleteListener(this, new OnCompleteListener&lt;AuthResult&gt;() {
                  @Override
                  public void onComplete(@NonNull Task&lt;AuthResult&gt; task) {
                      progressDialog.dismiss();
  
                      if (task.isSuccessful()) {
                          Toast.makeText(LoginActivity.this, "Login Successfull...Bingo...", Toast.LENGTH_LONG).show();
                          Intent i  = new Intent(LoginActivity.this, ProfileActivity.class);
                          i.putExtra("Email", firebaseAuth.getCurrentUser().getEmail());
                          startActivity(i);
                      } else {
                          Log.e("ERROR", task.getException().toString());
                          Toast.makeText(LoginActivity.this, task.getException().getMessage(), Toast.LENGTH_LONG).show();
                      }
  
  
                  }
              });
  
  
  }
  }
  </code></pre>