Discord.js Ban script

client.on('message', message => {

    if (!message.guild) return;


    if (message.content.startsWith('?ban')) {
      const user = message.mentions.users.first()

      if (user) {

        const member = message.guild.member(user);

        if (member) {

          member.ban({
            reason: 'They were bad!',
          }).then(() => {
            message.reply(`Successfully banned ${user.tag}, LOSER HAH! Get the ban hammer boi!`); // this is the message that will be.
          }).catch(err => {

            message.reply('I was unable to ban the member. Check if their roles are higher then mine or if they have administrative permissions!'); // if a user does not have permission to use a command on a user or as a member, this message will be send.
//** for my bot I would say message.reply(`${author.tag}, sorry, I was unable to ban this user! Check to see if there roles are above mine, or if this user is an admin!`)**\\

            console.error(err);
          });
        } else {

          message.reply('That user isn\'t in this guild!');
        }
      } else {

        message.reply('You didn\'t mention the user to ban!');
      }
    }
  });