app\models\Vendor::addVendorContact PHP Method

    public function addVendorContact($data, $isPrimary = false)
    {
        //$publicId = isset($data['public_id']) ? $data['public_id'] : false;
        $publicId = isset($data['public_id']) ? $data['public_id'] : (isset($data['id']) ? $data['id'] : false);
        if ($publicId && $publicId != '-1') {
            $contact = VendorContact::scope($publicId)->firstOrFail();
        } else {
            $contact = VendorContact::createNew();
        }
        $contact->fill($data);
        $contact->is_primary = $isPrimary;
        return $this->vendor_contacts()->save($contact);
    }