@Navid12 No, she is not entitled to a refund. By sitting on that booking, she precluded any other guest from staying last night. What the guest pays for is not just use of the property, but also guaranteed access to it. Similarly, venues don't refund your concert ticket just because you don't show up, and airlines won't refund your fare just because you didn't make it to the airport.
If you were a longtime host with many established reviews/ratings, I'd suggest firmly denying her absurd request. As a new host with only 1 review, your listing is more vulnerable to a retaliatory rating, so you might tread carefully. Perhaps as a small compromise, you could offer a token percentage of the first night as a rebate upon checkout, under the condition that the property is left in a clean state with no damage.
I would avoid presenting this as a "refund," and absolutely don't transfer the funds before the stay is over.