Kaltura_Client_Exception thrown

Invalid KS "YzBmYTE3YmRmN2U0OTc4MWFmNmY3OTA1ZjYxZjk0NjM4Mjk3OGRiYnwxMDE7OzE0NjcyNTI3MjQ7MjsxNDY3MTY2MzI0Ljg0OTQ7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"