How do you have identity issues in relation to the name "Sad"?
It's a yearly limit to stop members from changing their name too often.
Of course, this also does not mean you have to change your username once a year. I've had the same name since day 1.
If you have identity issues, I think the issue is more your fault and not because of your username... BTW, the username field when registering will tell you specifically not to use a name similar to your other online accounts, especially Neopets.
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