He always addresses me by my name

How to learn someone's name without asking them: " hey you have an odd way of spelling your name don't you?" "No" "well how do you spell it" "john". "Ohhhhh I thought it was jonn."

Ask to compare driver licenses

Ask your mailman.

Ask their name. They'll probably exasperatedly say their first name. Laugh, and say,
"No, no, I mean your last name."
Now you have both.

The obvious answer is to go through thier mail. Stalk them at every turn. Watch them interact with thier neighbors, and hope they let loose his name. Do not stop. Do not give up. This is your life now.

Heeeeyyyy.............n-neighbor person :)

I was convinced I knew our next door neighbours name and put a card through the door at Christmas addressed to Sheila and family, got one back from Shirley and Paul

Same, he has a weird name but he's very nice

Best way for me: Ask them to add their contact to your phone.

introduce him to some1