It is an other fun cultural context. I have Firstname Middlename Lastname. This or Lastname Firstname Middlename appear on somethings like credit card, ID, passport and official legal documents. But in normal live like receiving normal letters and so on it is just Firstname Lastname or Lastname Firstname. Even the order is fluid with Lastname Firstname being more formal.
And then some people have First-Name firstnames where either part is also a name, but whole thing is one Firstname... So calling someone with just First is often wrong...
Okay but is there any social situation where calling you by the middle name is the appropriate way? Except when you mom's angry like the other commenter suggested :) Is a patronymic a middle name, or a second (first, actually) last name?
And then some people have First-Name firstnames where either part is also a name, but whole thing is one Firstname... So calling someone with just First is often wrong...