Kaltura_Client_Exception thrown

Invalid KS "Nzc0NmRkNmI1NGI1MDg0ZjgwODdjZDllMzAwMTI4NmY1YzU3NTVjMnwxMDE7OzE1MDEwMDA3NTU7MjsxNTAwOTE0MzU1Ljg1MDk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"