Spark Registration - Class CreateUser does not exist

After Upgrading to Spark 2.0 and Laravel 5.3, which has been about 2 weeks ago, our registration has been broken (we're in development not production). However, I still need to fix this.

This is the error that is returned when I attempt to submit a registration form:

Class CreateUser does not exist

I had previously added an additional registration field, which worked prior to the 2.0 update. The weird thing is that the form will submit successfully if I remove the code to add the additional field:

Spark::validateUsersWith(function () {
  return [
      'name' => 'required|max:255',
      'type' => 'required|integer',
      'email' => 'required|email|max:255|unique:users',
      'password' => 'required|confirmed|min:6',
      'terms' => 'required|accepted',
    ];
});

Spark::createUsersWith(function ($request) {
    $user = Spark::user();

    $data = $request->all();

    $user->forceFill([
        'name' => $data['name'],
        'email' => $data['email'],
        'age' => $data['age'],
        'type' => $data['type'],
        'password' => bcrypt($data['password']),
        'last_read_announcements_at' => Carbon::now(),
    ])->save();

    return $user;
});

class SparkServiceProvider extends ServiceProvider
{
  ...
}

But I need this additional field. Just wondering if anyone else has run across this problem!