Kaltura_Client_Exception thrown

Invalid KS "MDRjMTI5MDZiZGU1NTZhOWU1NWFjMzEzYmYxMTE2NTc5MzQ3ZTM5YXwxMDE7OzE0OTA3MTg4MTY7MjsxNDkwNjMyNDE2LjAwMjU7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"