Unity 3D Service : in-app purchasing missing

Hey, I was trying to set up an in-app purchase in my game, but when I go to the unity settings (where it’s supposed to appear in-app purchase) it doesn’t appear, it appears all the other options, just this one doesn’t. What should I do?

Thanks

Did you follow the steps here:
https://unity3d.com/learn/tutorials/topics/analytics/integrating-unity-iap-your-game