title: Firebase Phone Auth is not working in flutter app neither in iOS simulator nor in a real device
body: <p>I have been trying and searching various methods to make Firebase Phone Auth to work in my flutter application. (There is an <a href="https://github.com/FirebaseExtended/flutterfire/issues/1102" rel="nofollow noreferrer">open issue</a> talking about conflicts between Firebase Cloud Messaging &amp; Firebase Phone Auth, but I am unsure if my issue is related to that. I do use Firebase Cloud Messaging which works perfectly fine.). </p>
  
  <p><strong>In iOS simulator</strong>, whenever I call <code>FirebaseAuth.instance.verifyPhoneNumber</code>, my app opens a web page for reCAPTCHA workflow, and returns back to the app. Then I see the error logs like below in <code>verificationFailed</code> callback. (It is expected to follow reCAPTCHA flow for iOS Simulator according to <a href="https://firebase.google.com/docs/auth/ios/phone-auth#enable-app-verification" rel="nofollow noreferrer">Firebase Phone Auth Doc</a>)</p>
  
  <pre><code>flutter: Instance of 'AuthException'
  flutter: {"error":{"code":403,"message":"Requests from this ios client application &lt;empty&gt; are blocked.","errors":[{"message":"Requests from this ios client application &lt;empty&gt; are blocked.","domain":"global","reason":"forbidden"}],"status":"PERMISSION_DENIED"}}
  </code></pre>
  
  <p>It is suspicious that error message is using <code>&lt;empty&gt;</code> as my application name, instead of my real app name (or default firebase app name which is __FIRAPP_DEFAULT), but I am unsure why that is happening.</p>
  
  <p><strong>In real iOS device</strong>, whenever I call <code>FirebaseAuth.instance.verifyPhoneNumber</code>, the app invokes <code>verificationFailed</code> callback again and I get the error with <code>verifyPhoneNumberError</code> as code and <code>Token mismatch</code> as error message. This is happening in both debug build as well as in release build.</p>
  
  <p>I am using following SDK &amp; library versions.</p>
  
  <ul>
  <li>Flutter SDK = 1.12.13+hotfix.5</li>
  <li>firebase_core = 0.4.3</li>
  <li>firebase_auth = 0.15.4</li>
  <li>firebase_messaging = 6.0.9</li>
  </ul>
  
  <p>Has anyone been able to get Firebase Auth Phone auth working in iOS? I am stuck in this limbo state because I cannot seem to search any info online related to this. I have setup iOS APN, GoogleService-info.plist, Google Cloud Credentials multiple times so far with no luck. (Given that Firebase Cloud Messaging works perfectly fine, I doubt it is an issue with credentials or APN setup.)</p>