Discord JS - Follow a user into a voice channel when they join

I'm trying to make my bot detect when a specific user joins a voice channel (any channel) and then follow them into that channel. I've attempted to read the documentation but it seems to be absolutely useless. And basically every other resource is out of date. I'd show you my code but there is pretty much nothing so far. So far, my bot can simply come online in the server. Please could anybody help? Thanks.

So far I have tried to use this code to simply detect anyone joining any voice channel:

client.on('voiceStateUpdate', (oldState, newState) => {
    if(newState.channelID === null) //left
        console.log('user left channel', oldState.channelID);
    else if(oldState.channelID === null) // joined
        console.log('user joined channel', newState.channelID);
    else // moved
        console.log('user moved channels', oldState.channelID, newState.channelID);
});

This, among many other solutions I tried, has failed to work. I have attempted various different methods to get a guild member based on what I've found in the documentation and in tutorials - but these have also failed.

Make sure you have the correct intents. You probably also want to set the correct permissions in the Discord Developer Portal for playing audio and such too.

This code should work:

import { GatewayIntentBits, Client, Events } from 'discord.js';

const client= new Client({
    intents: [
        GatewayIntentBits.Guilds,
        GatewayIntentsBits.GuildVoiceStates
    ],
});

client.on(Events.VoiceStateUpdate, (oldState, newState) => {
    if(newState.channelID === null) {
        console.log('user left channel', oldState.channelID);
    } else if(oldState.channelID === null) {
        console.log('user joined channel', newState.channelID);
    } else {
        console.log('user moved channels', oldState.channelID, newState.channelID);
    }
});