Undefined method routeNotificationFor() when using trait

Question

I'm using the Notifable trait from the docs in Laravel 10.

Notifications work fine when using the User model.

Using a different model I get this error in the logs:

production.ERROR: Call to undefined method App\Models\Contractor::routeNotificationFor() {"exception":"[object] (BadMethodCallException(code: 0): Call to undefined method App\Models\Contractor::routeNotificationFor() at /var/www/html/vendor/laravel/framework/src/Illuminate/Support/Traits/ForwardsCalls.php:67)

The Contractor model has:

use Illuminate\Notifications\Notifiable;

and 

use Notifiable;

on it as per the User model and docs linked above.. It also has an email field (not that I'm using atm).

Firing the notification:

# Usually using the relationship
#$contractor = $this->model->contractor;
$contractor = Contractor::find(1);

if ($contractor)
{
     $contractor->notify(new JobContractor($this->model));
}

get_class($contractor) at this point says it's a App\Models\Contractor class and $contractor is set. echo $contractor->email does output the address so it is an instantiated model instance.

What else can I check here? Checking the definition of the traits in VSCode they seem to check out.

My Contractor class use(s) Notifiable trait which use(s) RoutesNotifications which has a routeNotificationFor function in it.

Edit 1: To test it's not an issue with the Notification and Mailable I changed to the other method using the facade:

use Illuminate\Support\Facades\Notification;

if ($contractor)
{
    #$contractor->notify(new JobContractor($this->model));
    $user = User::find(1);
    Notification::send($user, new JobContractor($this->model));
}

That does work.

Edit 2: I too am using queues like this answered question. However this is the same queue. I have restarted Supervisor and the server.