title: I am trying to make a discord.js avatar command, and the mentioning portion doesn't work correctly
body: <p>I have an avatar command in my discord bot. When the user uses <code>h.avatar</code>, it outputs their avatar, which works fine. Whenever they try to use <code>h.avatar @user</code>, nothing happens. <br>
  Here is my code:</p>
  
  <pre class="lang-js prettyprint-override"><code> } if (message.content.startsWith(config.prefix + "avatar")) {
        if (!message.mentions.users.size) {
          const avatarAuthor = new Discord.RichEmbed()
        .setColor(0x333333)
        .setAuthor(message.author.username)
        .setImage(message.author.avatarURL)
          message.channel.send(avatarAuthor);
          let mention = message.mentions.members.first();
          const avatarMention = new Discord.RichEmbed()
          .setColor(0x333333)
          .setAuthor(mention.user.username)
          .setImage(mention.user.avatarURL)
          message.channel.send(avatarMention);
  </code></pre>