Extend Activity Log to have custom values stored in database

[exorgroup]

I need to extend the activity log by adding an additional field that is saved in the database. I tried to use an observable but the value is not being stored. Observable is being launched and works as intended. May I am missing something?

use Spatie\Activitylog\Models\Activity;
//use App\Models\Activity;

class ActivityObserver
{
    /**
     * Handle the Activity "created" event.
     */
    public function created(Activity $activity): void
    {
        //
        $data = array( $activity->log_name, 
                    $activity->description,
                    $activity->subject_type,
                    $activity->event,
                    $activity->subject_id,
                    $activity->causer_type,
                    $activity->causer_id,
                    $activity->properties,
                    $activity->batch_uuid,
                ); 
        $activity ->HASH = Security::hashText($data);
    }
}

[exorgroup]

I sorted this with tap activity placed in the model

 public function tapActivity(Activity $activity, string $eventName)
    {       
            $data = array( $activity->log_name, 
            $activity->description,
            $activity->subject_type,
            $activity->event,
            $activity->subject_id,
            $activity->causer_type,
            $activity->causer_id,
            $activity->properties,
            $activity->batch_uuid,
        ); 
        $activity ->HASH = Security::hashText($data);
    }