Kaltura_Client_Exception thrown

Invalid KS "MDlkZmUwNjBkMTMzNGUwZGViYTZjZTA3NmMwZDhkMTUyODRmMjA0NnwxMDE7OzE0NzUzMzYxMjk7MjsxNDc1MjQ5NzI5LjU3Mjg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"