Hi @Olivia19,
If Internet access is a requirement of your stay (as it is for 99% of us) and it is no longer available you can choose to cancel and book elsewhere. Whilst it could be quite reasonably out of the Hosts control they should be putting an effort in to find a work around.
Airbnb would be 100% fine with you cancelling it and if these conversations between yourself and the Host have been had via the Airbnb messages then a quick call to them will help solve it for you.
I'd suggest doing a quick check on alternative accommodation and then planning your next move in kind.
Hope it all works out for you.
Cheers,
Paul
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