Kaltura_Client_Exception thrown

Invalid KS "NzVmOTUwZWVlN2VmNjE0NjRkZDhjNWRkMGY1OGQxMDdkMWZlYjEwNXwxMDE7OzE0OTgzOTI0Nzc7MjsxNDk4MzA2MDc3LjQ4MTY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"