Kaltura_Client_Exception thrown

Invalid KS "Nzk3NzFhMjc3MDQ4MDg1ZTA2MWU5MzJjMDllNzc4ZjM0YWM4MTlmMnwxMDE7OzE0NzQ4NDQ3MDY7MjsxNDc0NzU4MzA2LjE1ODM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"