Why was the score of the USA-Finland hockey game changed at the last minute? Here is what happened

The USA women’s hockey team thought they had won 5-1 over Finland in their first group game, but as the team celebrated and walked off the ice, they were told to come back in a weird scene.
It turned out that 5-1 was not the final score of the match. With 2:20 to go, Finnish striker Susanna Tapani fired a shot on goal that appeared to hit the post and bounce.
The on-ice umpire waved his arms, signaling the puck had not gone in, and the green light behind the goal flashed, indicating play should continue.
Video of the game eventually showed the puck hit the post, but then went under the crossbar and into the net, giving Finland their second goal of the game.
The review began once play had taken place, but the result could not be announced until the next stoppage in play, which turned out to be the “end” of the game.
As a result, the goal was added to the tally and the teams had to return to the ice to play the actual 2:20 final of the contest, which went to no more goals scored as the United States won their first victory of the tournament.
For the curious, if another goal had been scored during this time, it wouldn’t have counted, as the game would have been reset to 2:20 after the second count.