Kaltura_Client_Exception thrown

Invalid KS "MjMwYTg4NDM3ODgzM2Y0MjE2ZjA3Yjg3NzU2MTc4NzkzZTI3YzE4ZXwxMDE7OzE1MDA2NTYzNzc7MjsxNTAwNTY5OTc3Ljk5MTk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"