Kaltura_Client_Exception thrown

Invalid KS "M2VhN2E4ZTkwZmIwMzhhMGU5YzJmZTlmZTY3ODI1YjJiNjIxMDVhN3wxMDE7OzE0NzQ4NjkyODY7MjsxNDc0NzgyODg2LjA3NTU7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"