title: Cannot fix Promise in react native Promise { "_U": 0, "_V": 0, "_W": null, "_X": null, }
body: <p>Why did I add Promise to the function it still gives an error ??</p>
  <p>I cannot call this function again with the parameter I give ??</p>
  <p>Get User by Uid in Fire.js file( I custom this file )</p>
  <pre><code> getUserbyUid = async ({ Uid }) =&gt; {
          return new Promise((res, rej) =&gt; {
              firebase.firestore()
                  .collection('user')
                  .doc(Uid)
                  .get()
                  .then(documentSnapshot =&gt; {
                      res(documentSnapshot.data().name);
                  })
                  .catch(error =&gt; { rej(error) });
          })
  
      }
  </code></pre>
  <p>in Feed.js i call it</p>
  <pre><code>  async componentDidMount() {
          await firebase.firestore().collection(&quot;Post&quot;).get()
              .then(querySnapshot =&gt; {
  
  
                  querySnapshot.forEach(documentSnapshot =&gt; {
  
                      this.setState({ dataPost: this.state.dataPost.concat({ ...documentSnapshot.data(), 
                      key: documentSnapshot.id, }) })
                      console.log(Fire.shared.getUserbyUid(documentSnapshot.data().uid)); &lt;= error this if i console.log(documentSnapshot.data().uid)) it will return a Uid 
  
  but If i call in above it will return  Promise { &quot;_U&quot;: 0,&quot;_V&quot;: 0, &quot;_W&quot;: null,&quot;_X&quot;: null,}
  
  
                  });
              });
      }
  </code></pre>