Kaltura_Client_Exception thrown

Invalid KS "N2M3MTRiYjkxNWE2ZWJiZGNhYjMwMWIyZDEyYzBlOWQxMTA4N2QwNnwxMDE7OzE0NzUxODM3MzU7MjsxNDc1MDk3MzM1LjI2OTY7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"