public function addContactToCampaign()
    {
        if ($this->contact->getId()) {
            // Add the contact directly to the campaign without duplicate checking.
            // Passing manuallyAdded as true is important, prevents cron from immediately removing the contacts.
            $this->addContactsToCampaign($this->campaign, [$this->contact], true);
        }

        return $this;
    }