Kaltura_Client_Exception thrown

Invalid KS "M2UwOTE1MWQxY2ZhOTVhNTBhZDU1ODZmN2EwMTQ3ZThiYTQxODQwYXwxMDE7OzE0NzUzODU1MDc7MjsxNDc1Mjk5MTA3LjE3NDc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"