normally it's have item free for new prayer but i don't have who know tell me please

Not quite sure of your meaning here. I am guessing you mean a new PLAYER, not a prayer. Either way, not sure what you mean here and what item you are talking about.

Do you mean the “add a friend, get 5 free gems?” If so, I believe it has to be someone new to Dragon City and they have to begin playing the game.

You can always submit a bug report, but you will have to be a little clearer with your meaning. Instructions are in my signature line.