index.js

const Discord = require("discord.js")
const bot = new Discord.Client()

bot.on("voiceStateUpdate", (oldState, newState) => {
  // Checking users new voice channel state and if the left channel has 0 members left.

  if (newState.channel == null) {
    let leftChannel = newState.guild.channels.cache.find((c) => c.name === `Personal Channel - ${oldState.channel.id}`)

    if (leftChannel == null) return

    if (leftChannel.members.size == 0) {
      return leftChannel.delete()
    } else return
  }

  // The channel the user has to join to get moved into their own channel
  if (newState.channel.id == 'YOUR "CREATE CHANNEL" ID') {
    // The initial channel creation and sending it to the correct category
    let userID = newState.guild.members.cache.get(newState.id)

    newState.guild.channels.create(`Personal Channel - ${newState.id}`, { type: "voice" }).then((channel) => {
      let category = newState.guild.channels.cache.find((c) => c.name == "YOUR CATEGORY NAME" && c.type == "category")

      channel.setParent(category.id)

      newState.guild.member(userID).voice.setChannel(channel.id)

      return channel.setName(`Personal Channel - ${channel.id}`)
    })

    // Checking users old state
  }
  if (oldState.channel == null) return
  else if (newState.channel.name !== `Personal Channel - ${oldState.channel.id}`) {
    let leftChannel = newState.guild.channels.cache.find((c) => c.name === `Personal Channel - ${oldState.channel.id}`)

    if (leftChannel == null) return

    if (leftChannel.members.size == 0) {
      return leftChannel.delete()
    } else return
  }

  // Misc checks to make sure that muting their mic or streaming etc doesn't remove them from the channel
  if (newState.streaming == true) {
    return
  } else if (oldState.streaming == true) return

  if (newState.selfDeaf == true) {
    return
  } else if (oldState.selfDeaf == true) return

  if (newState.selfMute == true) {
    return
  } else if (oldState.selfMute == true) return

  if (newState.serverMute == true) {
    return
  } else if (oldState.serverMute == true) return

  if (newState.serverDeaf == true) {
    return
  } else if (oldState.serverDeaf == true) return

  if (newState.selfVideo == true) {
    return
  } else if (oldState.selfVideo == true) return

  if (oldState.channel == null) {
    return
  }

  // Final older state checking
  if (oldState.channel.name == `Personal Channel - ${oldState.channel.id}`) {
    let leftChannel = oldState.guild.channels.cache.find((c) => c.name === `Personal Channel - ${oldState.channel.id}`)

    if (leftChannel == null) return

    if (leftChannel.members.size == 0) {
      return leftChannel.delete()
    } else return
  }
})

bot.login("YOUR DISCORD TOKEN")