Kaltura_Client_Exception thrown

Invalid KS "NmUzMTExNzIyNmQxYmMyZjE5NjE5YWU0OWU3YmQyMWFmMzJjZGRmZXwxMDE7OzE0NzUxODk1MDY7MjsxNDc1MTAzMTA2LjgyMDU7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"