Hotel Octagon in Dusseldorf

Booked a room for two. Only got bed sheets for one. The slatted frame on the side without sheets only existed with 4 pieces so my girlfriend crashed on the floor when taking place on the bed. Very dirty. We didn't stay the night, it was too awful. On a picture inside the room someone wrote down his mobile phone number. Seems like nobody cared. There is no breakfast in the hotel itself. You only receive a voucher for a bakery nearby. When you closed the room door there was a gap that can be used to look outside to the corridor and reverse (1-2 cm). Had to wait some time until someone appeared at the reception. Guy was very nice, appeared to be a temporary help. Said that they opened just this week, but the first ratings I found were from beginning of August. Searched for excuses I think. The manager called us an hour later and was very angry and said we left without paying. Very very unfriendly and we talked with the guy who was there and he said we can leave. He did not seem to be very much surprised by the way.