If you have set up a restricted profile on your tablet you should enable “Play Games” and [Our App] in the settings. Here is how you do that:
1. Go to Settings -> Users
2. Tap the gear icon next to the restricted profile
3. On the list of “App & content access” turn on “Play Games” and [Our App]
4. Log-in to the restricted account
5. Connect to the Internet
6. If the app was open during this process, quit and restart the app.
This will enable the IAP’s in your restricted profile.