The license you purchased for has been expired for a number of months. All add-ons share expiry dates with the parent license, so you have access to a version that was considered available when that license was expired. As such, extending your XF license would give you access to newer XFMG licenses as well.
If you want to do this, get in contact with us and we can do that without the XFMG extension cost being included. Alternatively, if you're not happy with this, uninstall XFMG from your forum, delete any downloads you have of it and get in contact with us for a refund.