How do I get my Discord bot to send a welcome message?

I've watched numerous videos, and followed examples online, and still can't get my discord bot to simply send a message upon a member joining. Maybe I'm missing out on an important update?

//require the necessary discord.js classes
const { Client, Intents } = require("discord.js");
const { token } = require("./config.json");

//create a new client instance
const client = new Client({ intents: [Intents.FLAGS.GUILDS] });

//when the client is ready, run this code (only once)
client.on('ready', () => {
    console.log("Online");
});

//sends user a welcome message upon joining
client.on('guildMemberAdd', member => {
    const channel = member.guild.channels.cache.get('921490782958014576');    
    channel.send("Welcome to the server!!")
});

client.login(token);

I get nothing. Nada. I've tried several different pieces of code. I've TRIPLE checked the permissions. This is very frustrating. I've tried unadding and readding the bot to the server. I checked up on the discord.js documentation and nothing seems to be wrong with my code. To me it seems as if the guildMemberAdd isn't emitting anything. I'm using notepad++ to edit my code. I feel I could be using something better for debugging purposes possibly.