Kaltura_Client_Exception thrown

Invalid KS "Y2U4ZTE3OGEwZTA0Zjc1MmM0YjI4MGY5NzU3MTQ2NTI0ZWJjYjg0ZXwxMDE7OzE0OTM1NTI1MDI7MjsxNDkzNDY2MTAyLjg5NzM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"