@Thomas-Scharrer Interesting. The route that I made has now changed and looks like yours now. If I turn the traffic overlay on it shows a black line to indicate a road closure.
I checked this on the TomTom MyDrive website and on Google maps and neither of them show a road closure. Just some roadworks on the roundabout.
The route is ok again if you use the Disable Seasonal Closures tool.
I know that this isn't the perfect solution but it works.
You can report road problems directly to the HERE map using this link: https://mapfeedback.here.com/#/report
I have already reported it but the more people that report it then the more likely that HERE will do something about it.