My brother and I (both under 13) are on the same family account and our parental controls are set to allow for true friends and chat. We both have plugged in each others true friends code but nothing happens. Why?
My first thought is that you or your brother is typing an 0 instead of a 0, or a 1 instead of an i. You may want to retry with multiple TF codes. (I have to do that myself sometimes with my room-mate.)
If you can't get it after 2 or 3 tries, or have tried copying the text and sending it to your brother via e-mail and having him paste it with similar results, you may want to send KI a trouble ticket with your account info and the code. (https://www.wizard101.com/CustomerSupport/game)
