How did you get to trade???
I would link you to the million live wiki page that had.... that information. But I can't seem to find that page in the new version of it.
I'm pretty sure I remember the steps correctly though.
1. Change your Gree region back to US.
2. Confirm your account using your normal phone number.
3. Enter the code sent by Gree.
3. Connect to a JP VPN to change your region back to Japan
4. You're done!
If you're the spending type, I think confirming makes it harder to buy points, but I'm not honestly sure. (because I don't spend)
Let me know if it works... I might add that to the wiki page