Purchased full Parallels Desktop for Mac Student Edition, won't activate, states need to buy again

I purchased a physical copy of Parallels Desktop for Mac Student Edition from my institution's computer store. It clearly states "Parallels Desktop for Mac Student Edition". I downloaded Parallels from the parallels.com/welcome-student, then entered the activation key and it states that it is a permanent license added to my account, but when I try to activate it it states "The previous activation key has not been accepted by the license server."

In manage licenses, it states that I have a permanent license and that the status is active, but then when I open the application, it states I have an active trial that will expire in 15 days, and that I can't activate the license (leading back to the previous mentioned error message) which then only prompts me to buy a full license from the website. I don't know what to do since I purchased the physical copy, I doubt they will allow me to return an opened copy of a download code.

 

Hi, We've checked your account and your' license key is OK. Just for check, could you please uninstall Parallels Desktop reinstall it again and try to activate it with your permanent license key.
Plz provide us with the results.