My contacts nearly all have US phone numbers. The explore.garmin.com contacts web page shows "United States" in the drop down box before the phone number. But it shows some numbers with the "+1" in front and others without. The edit link on the contact page won't change the number, and I don't know which version is correct anyway. Can someone please tell me (1) if it makes a difference, (2) which displayed version is correct and (3) how I change the number if I need to?