Hi @Claudia4279
In private mode I put in Kirchberg and you came up in 1st position for flexible dates for 2, 3 and 4 guests (2nd position for 2 guests). Your reviews are also great - not much you can change!
If I were you I would select a date range coming up soon and run a custom promotion. Monitor the views on the promotion and slowly drop the price by a very small percentage at a time until you get booked. Then use this knowledge to create another promotion for other dates. Hope it helps!