Kaltura_Client_Exception thrown

Invalid KS "MjVjODcwYzNjNTg5YmRlNzkwOWI5NDRkMDM5YzA4NzliMjA0YTE5MXwxMDE7OzE0NzU0MzAzNjE7MjsxNDc1MzQzOTYxLjM1Njg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"