Kaltura_Client_Exception thrown

Invalid KS "ZTBhMTMxNzMyYWFhYTJlNDRkMjE5YjExNDdiODQ0MjFjODc3OTA1OHwxMDE7OzE0NzUxODk3MDY7MjsxNDc1MTAzMzA2LjQ1NDg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"