[JamesBarney]

What if the situation were reversed, and I bought a wager only due to the fat fingering of my calculator, or I mistook one team for another or just had a brain fart.

Wouldn't it then be reasonable for them to give a refund?

[ambulancechaser]

A part to consider is whether the other party knew or should have known of a mistake.

It's not reasonable for FanDuel to assume a mistake there. However, if a customer purchased a bet on a game that had already happened it would be reasonable to assume a mistake had been made.

Mistakes happen and the law of contracts deals with them.

[Marazan]

Yes, and bookies do as long refund clients' mistakes as long as the price hasn't moved that much and it is before the event.

[JamesBarney]

Both which were not true of this interaction.