@Stacey177 I'm so sorry that this happened to you. As others have said, be persistant- you should not be charged for this reservation, obviously.
I don't understand why you wouldn't have read reviews before booking, though. Those reviews are there for the benefit of prospective guests, seems strange not to make use of them before committing to a booking.
Also, in the future, if a host is non-responsive, always contact Airbnb right away- they will attempt to make contact with the host, and if they are unsuccessful, they will usually find you another place to stay.And don't wait until just before arrival to communicate with a host- start communicating when you book- if you don't get responses, that's a red flag, and you should contact Airbnb.
And you should also contact Airbnb immediately if something like this happens- not wait up to 24 hours and then request a refund. Had you contacted Airbnb as soon as you arrived to find no host to let you in, they would have immediately cancelled the reservation for you and tried to find you alternative accomodation.