Problem with OAuth2 on discordjs.guide | discord.js - imagine an app | Page 1

I have copied the code from discordjs.guide 1 to 1 but get the following error back when authorizing:

TypeError [ERR_INVALID_ARG_TYPE]: The "string" argument must be of type string or an instance of Buffer or ArrayBuffer. Received an instance of Array
    at new NodeError (node:internal/errors:372:5)
    at Function.byteLength (node:buffer:735:11)
    at AsyncWriter.write (C:\Discord-OAuth2\node_modules\undici\lib\client.js:1611:24)
    at writeIterable (C:\Discord-OAuth2\node_modules\undici\lib\client.js:1572:19) {
  code: 'ERR_INVALID_ARG_TYPE'
}

#Problem with OAuth2 on discordjs.guide