@Elena3214 That's a tough one. The listing describes the sofa as a "sofa bed," but I can't tell from the photos whether that sectional sofa has a pull-out sleeping function. I also see that it's a new listing with only 4 prior reviews, so it's possible that you might be the first guests to have experienced the sofa situation.
If the bed arrangements were falsely advertised, that should be grounds for a full refund. But how easily you can get that depends on how closely you followed the instructions. If the message thread shows that you contacted the host to ask what's up with the sofa bed and linens, and they verified that it was actually just a plain old sofa, that would be the hook to advance your dispute. On the other hand, if you left without first giving the host a chance to rectify the problem, and it turns out that actually there was a pull-out bed and linens in there after all, you'd be out of luck.
I see that the "hosts" remotely manage 22 listings in several cities and describe themselves as a "group of students." That gives me the impression that they're not totally on the ball about the contents of the properties and weren't readily available to help you when you checked in. If my suspicion is correct, be sure to make a lot of noise about your efforts to contact them, and point to any unanswered messages from your check-in date as evidence that you did your due diligence.
