Kaltura_Client_Exception thrown

Invalid KS "MGRhZWJmMTczZTc3ZmEwNWU3M2YyMTA0YjJjYzUzODg0MzQ3MTZkMXwxMDE7OzE0OTg2NDgwNTI7MjsxNDk4NTYxNjUyLjY1Nzc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"