Kaltura_Client_Exception thrown

Invalid KS "MDE1ZTgxMDgzMGQ1MDI3NjYyMjg4ZjU5MjE3N2Q5YTcyYzdkNDAzNXwxMDE7OzE0OTMxMTkzOTE7MjsxNDkzMDMyOTkxLjgyODk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"