Factual error: The family supposedly left Ex-Yugoslavia (what part isn't made clear exactly) "because of the war", but the only conflict still going on there in 1999 (when the family is still there in the opening scene) was the NATO bombing of targets in Serbia in order to get the Serbs to lay off Kosovo, and that was long over by Christmas of that year.
Continuity mistake: When Santa tells Noelle he's anxious about inheriting his dad's role, the position of his arms is inconsistent between front and side shots.