You should never post your Order Number in public! Someone might easily steal your order.
From which country you are trying to activate from ? That error code usually indicates a problem when activating from a country Esellerate is not allowed to have business with, due to various legal restrictions for being an US company.
Some users from such countries got around this problem by activating using a proxy service, like this one:
https://www.hotspotshield.com/The free service should be enough, just for the activation.