Kaltura_Client_Exception thrown

Invalid KS "ZGFiYzM3YTRjZDBjNGFmMTcwODkwNDNlYWI5OWE5ZDQwYzllNGU5MHwxMDE7OzE0OTM1ODg2NTc7MjsxNDkzNTAyMjU3LjcyMTM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"