Kaltura_Client_Exception thrown

Invalid KS "MGNiMzA2NjMzOGFjYzY2ZjQzZGE5MmQ1YjdmY2U3OTIxNzNlMTVjZnwxMDE7OzE1MDEwMDA2MzA7MjsxNTAwOTE0MjMwLjc4OTM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"