Undefined Method setActionSource()

[asila96]

I'm trying to set up an event request per the documentation and examples, but I'm getting an error when I try to use setActionSource(). Am I missing something or is this an actual bug?

use FacebookAds\Api;
use FacebookAds\Logger\CurlLogger;

use FacebookAds\Object\ServerSide\Content;
use FacebookAds\Object\ServerSide\CustomData;
use FacebookAds\Object\ServerSide\DeliveryCategory;
use FacebookAds\Object\ServerSide\Event;
use FacebookAds\Object\ServerSide\EventRequest;
use FacebookAds\Object\ServerSide\Gender;
use FacebookAds\Object\ServerSide\UserData;
use FacebookAds\Object\ServerSide\Util;

....

$event_0 = (new Event())
                          ->setEventName($eventName)
                          ->setEventTime(strtotime("now"))
                          ->setActionSource("Website") // throws errors for some reason
                          ->setUserData($user_data_0)
                          ->setCustomData($custom_data_0);

array_push($events, $event_0);
    
$request = (new EventRequest($pixel_id))
                                          ->setEvents($events);         

Error Message in PHP logs: Error: Call to undefined method FacebookAds\Object\ServerSide\Event::setActionSource()