Need help with a registration code

I recently bought a code for the dawntrail expansion and when I go to try and put it in I get "The entered code cannot be activated at this time. Please try again during the validity period."
what does this mean and does anyone know what I can do to fix it?

I'm posting this on behalf of a friend that struggles with this issue.

Thank you for posting in the Final Fantasy XIV Technical Support Forums.

Unfortunately, the issue you are describing is something we are not able to assist with in the Technical Support Forums. In order to get the proper support, we advise your friend to contact the Square Enix Support Center.

Please be sure to contact the correct region for the Support Center that matches the region of the Square Enix Account in question.

With this being said, this thread will be moved to the 'Separate Support Required’ subforum as contact with the Square Enix Support Center is necessary to resolve the issue.

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