Kaltura_Client_Exception thrown

Invalid KS "MjRmZDNmNDY0YTBmY2E0MDhkMzBhYWQyN2RiNDIwYzE2NGNlNTQ5NnwxMDE7OzE0OTMzMjI2MzI7MjsxNDkzMjM2MjMyLjMwOTc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"