Hello @Sinead3
First of all you may need to repost as you have tagged your question onto the bottom of someone else's so most hosts who frequent these forums won't see it and therefore be able to comment.
I am sorry you had this experience. I have to say Airbnb are normally really good in these situations, cancelling the booking and would have given you a discount voucher towards your new accommodation and advice on what might be available through them.
Are you saying that Airbnb did not help you when you reported this within 24 hours of your arrival.
In terms of the accommodation you booked, I hope you flagged the host's listing.
By the way what sort of reviews did this host have for the listing? What sort of ratings were they given.
Personally I only book Airbnb accommodation with longstanding four/five star hosts with great reviews.
If you still haven't had a refund from Airbnb contact them via Twitter. This is a forum for hosts and not monitored by Airbnb.