There is income taxes due on winnings at a casino. The only way you could get a refund on such winnings is that taxes are withheld from your winnings that exceeded your tax liability.

Taxed as ordinary income and sourced to where earned, (Calif) for state purposes.

no they do not have to pay taxes on their winnings.

Since winnings are the opposite of losses, your question is very confusing. Perhaps your lottery winnings were stolen. If so, you can report the theft to the police.

California does not tax have a state income tax on lottery winnings. The federal withholding rate amount is 25 % to be withheld from the winnings amount.