Kaltura_Client_Exception thrown

Invalid KS "MzVjNDgwNjljMDRiOWY3ZDQ1NTA4MTNkZWIxNTI2ZDc4MGI0YTUwMXwxMDE7OzE0OTM0NjY5MTY7MjsxNDkzMzgwNTE2Ljg1NjM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"