Kaltura_Client_Exception thrown

Invalid KS "YzVmY2MwZGZhYjU3YzJiYjZkODVjMmNkNWVlODgzYjU2NTMzMWYwZXwxMDE7OzE0ODgwMTI1MzY7MjsxNDg3OTI2MTM2LjYxOTk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"