fatal error on Google CDN setting

Hi I changed the CDN setting from self hosted FTP to Google Drive and clicked on Save. Unfortunately, the W3 Total Cache dashboard and all setting product this error code: fatal error: Uncaught exception ‘Google_Auth_Exception’ with message ‘Could not json decode the token’ in /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/lib/Google/Auth/OAuth2.php:178 Stack trace: #0 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/lib/Google/Client.php(181): Google_Auth_OAuth2->setAccessToken(”) #1 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/CdnEngine_GoogleDrive.php(39): Google_Client->setAccessToken(”) #2 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/CdnEngine_GoogleDrive.php(31): W3TC\CdnEngine_GoogleDrive->_init_service(”) #3 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/CdnEngine.php(55): W3TC\CdnEngine_GoogleDrive->__construct(Array) #4 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/Cdn_Core.php(559): W3TC\CdnEngine::instance(‘google_drive’, Array) #5 /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/Dispatcher.php(210): W3TC\Cdn_ in /home/wp_ecvnbz/cafoundationfund.org/wp-content/plugins/w3-total-cache/lib/Google/Auth/OAuth2.php on line 178