title: React Native Post Request via Fetch throws Network Request Failed
body: <p>I've came across the following error.
  At the moment I developing an Android App with React Native therefore I'm planning to use fetch for doing a post request for me.</p>
  <pre><code>fetch(&quot;https://XXreachable-domainXX.de/api/test&quot;, {
      method: &quot;post&quot;,
  
      body: JSON.stringify({
        param: 'param',
        param1: 'param',
  
      })
    })
    .then((response) = &gt; response.json())
    .then((responseData) = &gt; {
      ToastAndroid.show(
        &quot;Response Body -&gt; &quot; + JSON.stringify(responseData.message), ToastAndroid.SHORT
      )
    })
    .catch((error) = &gt; {
      console.warn(error);
    });
  </code></pre>
  <p>The app now throws an error:</p>
  <blockquote>
  <p>TypeError: Network request failed</p>
  </blockquote>
  <p>When I change the code to a GET-Request it's working fine, in the browser with a window.alert() as a return it's cool and also the Chrome extension Postman returns data correctly.</p>