The law does not require refunds to a party of a deposit if that party was the one which cancelled the service. Since your daughter cancelled the wedding reception, she and you would only be entitled to a refund if the reception hall had voluntarily adopted a policy of providing refunds and you fully complied with (and the situation called for under) the policy's  terms and requirements. From what you write, you would only seem to be entitled to a 50% refund if the date is subsequently filled, otherwise nothing. Had the reception hall canceled, the situation would be very different--in that event, you would likely be entitled to a full  refund.