Discord.JS 11.4.2 "user.createdAt" comes back as "undefined"

Question

I'm trying to make a userinfo command in DiscordJS 11.4.2 Here's a sample of my code:

module.exports = {
    // CMD INFORMATION
    name: 'userinfo',
    aliases: ["whoami"],
    description: "Gets ur user info",
    category: "Information",

    // THE ACTUAL CODE
    execute(client, message) {
message.channel.send(`your info:\nuser id: ${message.author.id}\nyour username and tag: ${message.author.tag}\nyour avatar (URL): ${message.author.displayAvatarURL}\nyou joined the guild at ${message.member.joinedAt}\ncake day: ${message.member.createdAt}`)
        

    },
};

What it comes out as:

your info:
user id: (Insert UID here)
your username and tag: Winfinity#9884
your avatar (URL): https://cdn.discordapp.com/avatars/756176319829508207/251b24bc5366d0a3fe37fc7f36f7fadf.png?size=2048
you joined the guild at Sat Sep 26 2020 03:25:39 GMT+0000 (Coordinated Universal Time)
cake day: undefined