title: Discord.js voiceStateUpdate not registering properly
body: <p>I have this piece code for discord.js copied from reddit which is supposed to detect if user has joined or left the channel but it sends leave notifications only no matter if someone joins or leaves the channel. About a year ago when I last tried this same code, it worked well, but now it doesn't.</p>
  <pre><code>bot.on('voiceStateUpdate', (oldMember, newMember) =&gt; {
    let newUserChannel = newMember.voiceChannel
    let oldUserChannel = oldMember.voiceChannel
  
    if(oldUserChannel === undefined &amp;&amp; newUserChannel !== undefined) {
       // User Joins a voice channel
      console.log('join');
  
    } else if(newUserChannel === undefined){
      // User leaves a voice channel
      console.log('leave');
  
    }
  })
  </code></pre>
  <p>Has discord.js changed or what am I doing wrong? If you want the whole code, I can send it aswell.</p>