This is a user forum and not a direct channel into either Adobe Customer Support or Adobe Technical Support.
Please call Adobe Customer Support directly. They are the only organization that can assist you. Make sure you have all relevant information about your transaction when you call.
If by certification code you mean serial number, there is none for CC. You need to log in through the desktop app usng the Adobe ID that you used for the purchase.
Unless the OP actually did buy CS6.