Kaltura_Client_Exception thrown

Invalid KS "ZjBlYWRlMjg1MzBkZjZkYzAzNWNmNWExMGI4NjU5ZjMwMDYwMzQ2YnwxMDE7OzE0NzQ5NDM3NzM7MjsxNDc0ODU3MzczLjI2NDE7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"