public function updateContactDatafieldsByEmail($email, $dataFields)
    {
        $apiContact = $this->postContacts($email);
        //do not create for non contact id set
        if (!isset($apiContact->id)) {
            return $apiContact;
        } else {
            //get the contact id for this email
            $contactId = $apiContact->id;
        }
        $data = [
            'Email' => $email,
            'EmailType' => 'Html',
        ];
        $data['DataFields'] = $dataFields;
        $url = $this->getApiEndpoint() . self::REST_CONTACTS
            . $contactId;
        $this->setUrl($url)
            ->setVerb('PUT')
            ->buildPostBody($data);

        $response = $this->execute();
        if (isset($response->message)) {
            $message = 'ERROR: UPDATE CONTACT DATAFIELD ' . $url . ' message : '
                . $response->message;
            $this->helper->debug('updateContactDatafieldsByEmail', [$message]);
            $this->helper->debug('updateContactDatafieldsByEmail', $data);
        }

        return $response;
    }