Please go to the My Account -> My Profile section of this site. Your Subscriber ID looks to have changed, which can happen if you update your password or some other less common events. Please get the new Subscriber ID and enter it into the JFBConnect configuration area. Then, the Update Manager should work.
Alternatively, if that doesn't work, you can always download the latest release from the My Downloads area of this site and upload onto yours. Then, we'll gladly help work through any other issues you may have.
Thanks,
Alex