If Trivago showed you the wrong pictures of a hotel, you should take screenshots of them and send them with your ticket confirmation.
Trivago does not own the ads, so you should report the problem to both the booking site shown on your confirmation and Trivago's Help Center.
When you contact them, say that the pictures of the hotel didn't do it justice and ask for either a refund, a change to your reservation, or compensation, based on the situation.
If you're already at the hotel, ask the front desk to write down that the property doesn't look like the pictures that were offered. This will help your case.
If neither Trivago nor the booking site replies, you can contact Xolvie to get things fixed.
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