You might be an adult, your profile states this and you haven’t set up parental controls on your Wii U, but you can still not buy age restricted games on your Wii U if you live in Europe, here is a translated quote, from an email the source received from Nintendo:
Dear customer, we would like to let you know that Nintendo has always aimed to offer gameplay experiences suited to all age groups, observing carefully all the relevant regulations regarding content access that are present in the various European countries.
We have thus decided to restrict the access to content which is unsuitable to minors (PEGI) to the 11 P.M. – 3 A.M. time window [...]
Dear customer, we would like to inform you that it is an additional precaution to make sure that minors cannot access content which is inappropriate for their age
The source also stated this:
Note: my birthday is correctly set in my NNID account, I did mention this fact to Nintendo’s customer support and I also specifically asked if this measure should affect a console with no parental controls or parental controls without restrictions (tried both kinds of settings). I wanted to make sure that it was neither a glitch nor something due to a mistake I might have made configuring my account. It turn out, as you can see in their answers, that not… it is part of a clearly stated internal policy.
Frankly, I think this is a paternalistic measure which does not instill confidence in their child accounts and the parental controls their platform offers. Also, it does not really respect me as an adult to be responsible and use them to make sure that a child (which my wife and I do not yet have) does not access contents which are not right for his age.
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