Kaltura_Client_Exception thrown

Invalid KS "MjMzYTliNGI0Nzg1YjZlNTBlNThhYmMxYmVjODQ0YmM0ZjhiOTBhM3wxMDE7OzE0NzUxNjQ3OTI7MjsxNDc1MDc4MzkyLjI1OTQ7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"