Kaltura_Client_Exception thrown

Invalid KS "MDM3NGVkNmVhZmNkZTRjYjgwZjU1YTdjZGVhZDI2Nzk1ZmNhM2UwN3wxMDE7OzE0NzQ4NjI3ODA7MjsxNDc0Nzc2MzgwLjcxNDY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"