First, you should never post your order number in public, since someone knowing your email might steal your serial numbers. Questions about orders should always be made by email for this reason.
In any case, it's not very clear what do you mean with "serial number doesn't not work". Do you mean you see some error message about it ? If yes, which one ? Again, best to use email, because we might require to exchange data about your order you surely don't want to disclose in public.
