Have you checked your licence on your
YoYo Account to make sure that they are available? In the "Licences" section you should see all your applicable licences. If it doesn't show up there then you will need to
contact the helpdesk (select YoYoGames.com & YoYo Account" as the issue being reported) and request support for the issue as there is nothing that we on the forum can do - note that it will be monday before anyone sees your ticket as YYG don't have support at the weekend currently. If they ARE on your licence, then make sure you are logged in to the correct YoYo Account when you start GMS2, and if
that is all correct then I'd uninstall GMS and then download and install again, just to make sure you have the most up to date version.