Meta box License invalid

Hi,

I have the following message appear in WP-Admin.

Warning! Your license key for Meta Box is invalid or expired. Please fix it or renew to receive automatic updates and premium support.

Also when I visit the license page here: ../wp-admin/admin.php?page=meta-box-updater
it is asking for the license twice. But it doesn't matter how i enter my license in the top box, it still reports this error. How can I stop this from happening?

thanks,
John.