Hi there.
Welcome to the Three Community.
Changing those kinds of settings can't be done by the user, however the team can assist in stopping you from making international calls.
If you want easier control of it though, the best thing to do would be to place a spend limit on the account using My3, this means that if an international call is attempted, it won't be able to connect since the spend limit would prevent it. If you want to do that, you can just set the limit to £0 in the My3 app.
Pete.
