User ID to Username#Discrim

[Atharvnadkarni]

I am trying to make a discord bot with discord.js, but I have a problem with the ban and kick commands.

When a person says !ban @athroid, I want the bot to respond with "athroid#9322 banned successfully". I have a MemberTarget variable with the user ID, and I want to convert it into username and tag (like 792330397307895818 to athroid#9322).

Here is my code:

if (message.member.roles.cache.some(r => (r.name === "Moderator" || r.name === "Administrator"))) {
             const member = message.mentions.users.first();
             if (member) {
                 const MemberTarget = message.guild.members.cache.get(member.id);
                 const MemberString = MemberTarget.toString();
                 MemberTarget.kick();
                 message.channel.send(`${MemberString.tag} has been kicked successfully.`).catch(error => console.error(`Error occured; ${MemberString.tag} was not kicked.`));
             } else {
                 message.channel.send("Sorry, you did not mention a valid user to kick.");
             }
         } else {
             message.channel.send("Um.. it looks like you don't have the right permissions. In order to get the permissions, DM your server owner to kick the user.");
        }

But this happens when I run the bot:

It should say AtharvNadkarni#4244, not "undefined".

But nicely enough, my alt is removed from the server:

But why does it say "undefined"?

If I could, I would post the question on StackOverflow. But sadly, I cannot do it for 2 days because of my recent downvotes. Can you help me?

I need text in my question, so don't say I have to go on Gist.

[kyranet]

But why does it say "undefined"?

Because MemberString.tag is similar to doing '81440962496172032'.tag, and the tag property does not exist in strings.

What you want to do is MemberTarget.user.tag.