Kaltura_Client_Exception thrown

Invalid KS "MDk5ZmY1MGI3MGRjZTM2YmNkOWJlNTkxODFmM2Q3OTNkOGZkMGYzMHwxMDE7OzE0NzIxODcwMzM7MjsxNDcyMTAwNjMzLjE4NTE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"