What does No Action mean in betting?

No Action means the bet is void and should be settled as a refund. In other words, it does not count as either a win or a loss.

When does this happen?

This status appears if the event does not take place, the market conditions change, a participant does not start, or a bookmaker rule makes the bet void. For the player, the meaning is simple: No Action does not produce a return, but it does not result in a loss either. The money is usually returned to the account balance.