If you live close to the Canadian border your cell phone may be pinging a Canadian tower. In some areas their coverage is better then ours and this may show up as an international call even though you never actually called anyone in Canada.
Some of our Border Patrol Agent up north were complaining about it. Sorry I can't remember how they got it resolved.
That used to happen to me when I was at my parents home (a couple hundred yards from the border.)
There wasn’t much I could do about it. So I sold their home.
What? The US has borders?
I’m in TX.