It looks like I have some weird behaviour with the License key of the plugin.
In the WP admin, I get this message: "Warning! Your license key for Meta Box is invalid or expired. Please fix it or renew to receive automatic updates and premium support."
In the Meta Box menu, the submenu to the License page seems to be duplicated.
On the licence page, I have 2 field for the Licence Key. When I fill them with the licence key from the My Account page on metabox.io website I get the message "The link you followed has expired.".