It's really rare that it happens, but the players of the Canadiens were never able to return home after the game against the Capitals.
So, they are stuck in the United States and had to spend the night there. They will only be able to return when the issue is resolved.
"The Montreal Canadiens stayed in Washington after the game, due to an issue with the plane that was supposed to bring them back to Montreal last night."
- Renaud Lavoie, TVA Sports
Indeed, a problem with the plane prevented them from taking off. We know that when there is any doubt in aviation, there is an immediate and rigorous inspection.