Atlus has pulled Citizens of Earth from the Nintendo eShop temporarily due to an exploit found after it was made available through Humble Bundle.
Exploit in Citizens of Earth 3DS found, game pulled from eShop
According to the company, the bug in the 3DS version prevents the title from being run normally, but allowed users to run unsigned code in its place.
This is basically a backdoor for homebrew which is being called Humblehax by users after being part of the Friends of Nintendo Humble Bundle.
Atlus hasn't provided information on when Citizens of Earth will return to the eShop. Those who have yet to claim the Humble Bundle code for the 3DS version will find it will no longer work.
It's being reported that the Wii U code is working fine, so those who bought the bundle have two choices: claim the Wii U code or wait on the 3DS version to be made available once more.
Thanks, Nintendo Life.