Kaltura_Client_Exception thrown

Invalid KS "MDMzNGY1ZGNhYmI3ZTk2NzliMWI2YzlmN2UwYmQ0ZDIyMTMwMTlhZXwxMDE7OzE0NzUyMDE2NDk7MjsxNDc1MTE1MjQ5Ljc2MzI7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"