I am always bemused by how many (generally non-US) people in a global org will call me by my last name, even though *everybody in the org globally* has a "LastName, FirstName" presentation in chat, email, etc. Like, it's absolutely consistent (modulo the practice in some Asian countries for someone's name to begin with the family name and then go to the given name), and I'm just surprised how many people trip over something that's a highly consistent convention that has never changed.
@Biggles @darkuncle It is not necessarily a misunderstanding. More probably a cultural issue. When I was little, in France, teachers would call us by our last name -- only your own family or your close friends would use the first name. In town, people would mention my father as "Mr. Huitema, fils", to differentiate from my grandfather, "Mr. Huitema, père". Add son or father qualifiers instead of using the first names. Very common.