diff --git a/server/Game.js b/server/Game.js
index 18da51d..2229a65 100644
--- a/server/Game.js
+++ b/server/Game.js
@@ -67,6 +67,7 @@ function handleInput(gameId, playerId, input) {
 function persistChangedGames() {
   for (const game of GameCommon.getAllGames()) {
     if (game.id in changedGames) {
+      delete changedGames[game.id]
       fs.writeFileSync(`${DATA_DIR}/${game.id}.json`, JSON.stringify({
         id: game.id,
         puzzle: game.puzzle,