title: Joining a twilio channel with a user who already exists
body: <p>I have a React Native app which uses the Twilio Chat API to connect to a channel. I am using this repo: <a href="https://github.com/twilio/TwilioChatJsReactNative" rel="nofollow noreferrer">https://github.com/twilio/TwilioChatJsReactNative</a></p>
  
  <p>I am using <code>this.generalChannel.join()</code> to join my general channel. This works for any new user.</p>
  
  <p>I have the token generator running in the background as per the documentation in the readme of the repo.</p>
  
  <p>However, when I try to login with an existing user's name, I get an error with the <code>statusText</code> of 'Member already exists'.</p>
  
  <p>How can I log in to my Twilio Chat channel with an existing user?</p>