ZenHotels Booking Not Found at the Hotel – No Support or Refund for Extra Costs

I used ZenHotels to book a standard room in a hotel in Berlin because their price was about 27 dollars cheaper than another booking site I was comparing. Before paying, I carefully checked the room details to make sure I was booking the same type of room and the same conditions. I completed the reservation and shortly afterward I received the confirmation from ZenHotels. However, when I arrived, the hotel could not find my reservation in their system. Because of this, I was unable to stay there and had to go to another hotel instead. This situation caused both inconvenience and additional costs, and it completely canceled out the benefit of choosing ZenHotels for the lower price. I wrote to ZenHotels support about the missing reservation, but I did not receive any response. I expect ZenHotels to investigate why my reservation was not transmitted to the hotel, to explain clearly what happened, and to compensate me appropriately for the inconvenience and the extra expense of having to find another hotel at the last minute.