I never contacted anyone out of the country.
Do calls show up on your bill or account?
If you were on the phone at the time you got close to the internation border, the cell tower across the order could have picked up your call for a few minutes.
Without any details given from your post I'm only guessing.
Yes jav6, international calls do show up on your bill. Are you disputing your international calls? Did you travel outside the country?