Kaltura_Client_Exception thrown

Invalid KS "YWQyY2IwZDI1M2YzOWUxNjJjNjlmZGNkNWNmZGRhYzI2MzIxMThhZXwxMDE7OzE0NzUyMTk2Mjg7MjsxNDc1MTMzMjI4LjM0ODc7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"