title: FirebaseAuth.getInstance().getCurrentUser() returns previously logged out user
body: <p>I have Android app which uses FirebaseAuth and FirebaseDatabase functionalities. Everything was working fine. </p>
  
  <p>During last week I was working with one user (user 1) as an admin of the app and yesterday I registered another user (user 2) as a normal user(not admin).</p>
  
  <p>Since all my admin functionalities were working fine, I never logged in as the user 1 again. However I had to uninstall my app today and by that time I was logged in as user 2.  </p>
  
  <p>When I reinstalled it again, I was automatically logged in as user 1 for some reason. So I logged out and logged in as user 2 again and uninstalled again. The same thing happened again and again. </p>
  
  <p>I checked the user ID I am getting from the FirebaseAuth and its the user 1's user ID  which I had logged out previously.</p>
  
  <pre><code>FirebaseAuth auth = FirebaseAuth.getInstance();
  if(auth !=null)
  {
      String uid = auth.getCurrentUser.getUid();
  }
  </code></pre>
  
  <p>Please help me to solve this issue and I have added my logged out code below.</p>
  
  <pre><code> AuthUI.getInstance()
      .signOut(ShopHome.this)
      .addOnCompleteListener(new OnCompleteListener&lt;Void&gt;() {
          public void onComplete(@NonNull Task&lt;Void&gt; task) {
             // Code for login Activity              
           }
      });
  </code></pre>