Continuity mistake: When Gibert is reprimanding the police, you can see a clock in background. It reads 11:55, but when the scene ends, the clock still reads 11:55. The scene lasts at least three minutes and the clock didn't move. (00:29:20 - 00:31:50)
Revealing mistake: When the policemen are pursuing the Santa Claus gang in their Bigfoot, one of the police cars has 5 people in it. It falls in a pool and there are only 2 people, and if you watch closely, they are dummies. (00:37:30)
Continuity mistake: When Daniel goes to meet Lilly, he puts pregnancy test behind his ear. The pregnancy test changes its position in the following scene. (00:38:35)
Factual error: The movie depicts Tignes-Val-d'Isère as the closest ski resort from Switzerland. This is actually not the case as if you cross the border here, you end up in Italy, over 60 km away from Switzerland. The closest ski resort from Switzerland in France is actually Chamonix.
Continuity mistake: When Daniel and Emilien find the Santa Claus gang's hideout, Emilien opens the door and falls out into the snow. From the outside shot you can see the taxi has got wheels when they were changed into tracks earlier.
Plot hole: When Qiu is leaving Emilien, she ties him to a chair, sitting on a raised platform. This is to make it possible for the big ball to hit Emilien. But, when Daniel arrives, Emilien is able to throw himself into the trunk, which means, that if Daniel didn't show up, Emilien could have just thrown himself to the floor instead. So if he would be off the raised platform, he would never have been hit by the big ball in the first place.
Continuity mistake: When the Santa Claus gang is being pursued by the policemen, they pass through a house with their bigfoot. There is a lot of debris on the ground but when the police cars pass, the debris are beside the road.
Revealing mistake: When the police cars passes through the broken home, look at the floor: it is actually gravel.
Suggested correction: Look closely: this is actually carpet.
Visible crew/equipment: When the police cars are bumping on each other in front of the pool, the microphone is visible in some shots.