I have fallen in this trap too. 2. january 2022 I was blitzed 46 km/h. I was convinced that in this broad street the speed limit was 50 km/h.
Neither I or my passengers had noticed signs for speed limit 30 km/h. I dont understand this.
I have read that this control site earns more than 1 million Euros pr. year. Really a tourist trap. I think 98,50 Euros is a high tourist tax.
Otherwise we had a nice stay in Hamburg
Best regards Frank