Kaltura_Client_Exception thrown

Invalid KS "ZTU4MjM5MGI5NDE1YTVmNzU1NjE2ZDM2MjEzZmIwZDM4M2I3ZmYzZHwxMDE7OzE0OTU3MDA5NDg7MjsxNDk1NjE0NTQ4Ljg0OTM7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"