When you forget someone’s name, say, “I’m sorry, what was your name again?”
They will typically respond with their first name, albeit somewhat hurt that you forgot.
Then, emphatically reply, “No, no…your last name.”
Much relieved, they’ll happily oblige.
You’ll now have their first and last name without feeling as if you’ve insulted them.
Works every time.
And it’s also a good idea to repeat it back to help you remember.