Kaltura_Client_Exception thrown

Invalid KS "MTI1MWE2MDA5OTdmZmExYjQ0NTZjMTIyYWI2NmVjYWM2ZmY2OGQxY3wxMDE7OzE0NzU0NDg0NDg7MjsxNDc1MzYyMDQ4Ljk5MjM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"