If not, time for a charge back with your card provider.
I've done it multiple times when a vendor wasn't behaving fairly and it always went through.
I don't recommend doing it to a vendor you plan to have business with again in the future as they might ban you (eg food delivery apps)
It’s too risky tbh.
Fine, already pulling up a map to Enterprise, "just give me a refund".
"Sorry sir, prepaid rentals are non-refundable".
So you take my money, refuse to give me a car, and want to keep my money? No. Let's talk about chargebacks.