Call to undefined method Illuminate\Notifications\Notification::send()

Instead of:

use Illuminate\Notifications\Notification;

you should use

use Notification;

Now you are using Illuminate\Notifications\Notification and it doesn't have send method and Notification facade uses Illuminate\Notifications\ChannelManager which has send method.

Using this use Illuminate\Support\Facades\Notification;

instead of this use Illuminate\Notifications\Notification;

solved the problem for me.

Hope this helps someone.