I bought the retail Collecters Edition from Amazon, everything origninally packed, scratched open the Codecard, enter the Code and its Invalid, already made a ticket in the Support Section 5 hours ago. Its the standart 18 digits retail Code. I checked like 10 Times always entered the same Code as on the Gamecard.

Have the same issue, but with the day 1 edition.
It seems bandai misprinted those cd-keys, so if anyone got an not working cd-key, chances are that you got a misprinted one.

Unsure who will be faster with key replacement, GoG or the store where it has been bought.

My store already said they have asked for a cd-key replacement, but it takes time, your store is different, so try asking Amazob in your case, might be faster.