Column 'type' not found

Question

Good afternoon. The following code returns a weird error. I've looked at https://developer.salesforce.com/docs/atlas.en-us.api.meta/api/sforce_api_objects_attachment.html as a guide and from what I can tell, all of my settings are configured appropriately. Any reason why it's returning a weird error? usually it references a line in my code that returns the error but for some reason it does not. Is this because the error does not occur within my code?

var jsforce = require('jsforce');
var conn = new jsforce.Connection();
const fs = require('fs')
require('dotenv').config()
user = process.env.USER
pass = process.env.PASS

conn.login(user, pass, function(err, res) {
  if (err) { return console.error(err); }
  fs.readFile('2d.png',function(err, image){
    if(err){return console.log(err)}
      base64data = new Buffer.from(image, 'base64')
      conn.sobject('Attachment').create({
        ParentId: 'a7L3o000002J0YW',
        Name: '2d.png',
        Body: base64data
       }, function(err,res){
         if(err){return console.log(err)}
         console.log(res)
       })
    })

  })

Error:

INVALID_FIELD: No such column 'type' on sobject of type Attachment
    at HttpApi.getError (C:\Users\paulp\Desktop\Projects\JSForce Playground\node_modules\jsforce\lib\http-api.js:250:13)
    at C:\Users\paulp\Desktop\Projects\JSForce Playground\node_modules\jsforce\lib\http-api.js:95:22
    at tryCallOne (C:\Users\paulp\Desktop\Projects\JSForce Playground\node_modules\promise\lib\core.js:37:12)
    at C:\Users\paulp\Desktop\Projects\JSForce Playground\node_modules\promise\lib\core.js:123:15
    at flush (C:\Users\paulp\Desktop\Projects\JSForce Playground\node_modules\asap\raw.js:50:29)
    at processTicksAndRejections (internal/process/task_queues.js:79:11) {
  name: 'INVALID_FIELD',
  errorCode: 'INVALID_FIELD'
}