Hi alexarnoldi,
I am not with Laminar Research;just a flight simmer.
I bet you have purchased from somebody or business known as g2a. This business has nothing to do with Laminar Research. It is a 3rd party reseller. Have a look at the following link at https://questions.x-plane.com/20112/do-not-buy-by-g2a
If so, you, like many others in this forum have been scammed, duped, conned and so on into the purchase This business is supplying stolen installation codes that last a very short time and subsequently give you the answer you have received.
You will need to contact the seller and try and get you money back. Some future flight simmers have been successful. If and when you sort the problem purchase X-Plane from the developers ie Laminar Research. Support the official and original developers. Don't consider a Steam version as that product is a 3rd party hybrid that is slow to provide updates.
Hope this answers your problem
Glenn