It's a bit different from MC-12190

1. Open a world with scoreboard objective. The world should be made in earlier version. Otherwise, because of MC-12190, I cannot demonstrate this bug.
2. Earn score. By command or kill something or suicide yourself...
3. Close the world and restart that world again.
4. Tadada! Your all score has became zer0!

Well.... Because of this, I cannot play Hypixel's map ;_;