If your Nintendo code is showing as not valid there are several possible reasons. Common causes and fixes:
Wrong region — Nintendo codes are region locked. A US code will not work on a European Nintendo Account and vice versa. Check your account region at accounts.nintendo.com → Profile → Country/Region and make sure it matches the region of your code.
Typo in the code — Nintendo codes are 16 characters in the format XXXX-XXXX-XXXX-XXXX. The letters I, O, and Z are never used — if you see what looks like one it is actually a number (1, 0, or 2). Try entering the code again carefully or copy and paste it if you received it digitally.
Code already redeemed — if the code was already used on another Nintendo Account it will show as invalid or already used. Check your purchase history at accounts.nintendo.com → Store → Funds and Payment Methods → Purchase History to see if it was redeemed on your account previously.
Code expired — some Nintendo codes have an expiry date. Check any documentation that came with the code for an expiration date.
Code not yet active — some codes are not activated until a specific release date. If the game or content has not been released yet, wait until the official release date and try again.
Code not activated at point of sale — if you bought a physical card from a retailer, it may not have been activated correctly at checkout. Contact the retailer with your proof of purchase.
