public function get_lists(){

		if(empty($this->get_constant_contact_access_token())){
			return array();
		}

		$url = "https://api.cc.email/v3/contact_lists";

		$header = array(
			"Authorization" => 'Bearer ' . $this->get_constant_contact_access_token()['access_token'] ?? '',
			'content-type'  => 'application/json'
		);

		$response = wp_remote_get( $url, array( 'headers' => $header, ) );

		$token_request_data = json_decode( $response['body'], true );

		if (isset($token_request_data['error_message'])){
			return array();
		}

		return $token_request_data;

	}