I cannot tell which of your licences are for full products and which are for Crossgrades / Upgrades. But perhaps your Maxgraded Total Studio 2 Max is now no longer licensed?
If you have any Crossgrades / Upgrades then you must have a Qualifying Product for those. The same goes for your buyer. if you transferred a Crossgrade/Upgrade then he/she must have a suitable Qualifying Product for that transferred licence to work.
The best thing to do is contact
Sales/Account Support, via here, with all the details. You will be able to search the FAQs first, but if they do not resolve your issue, there is a
red button link to the Support form. Sales.account Support can look at your Account and your buyer's Account and see what's going on.
Response time aims to be within 2 working days (US (East Coast) Business hours, generally), but in the current circumstances please allow some more time.
Administrators and Moderators here cannot access your Account.