Hey @Ulrich_Gressler,
Thanks for taking the time to write in, it’s great to see you on community again!
Before being able to better dig into your issue, please edit your original post to fill in more details on your setup. The more specific you can be, the better it will help the support team pin down potential solutions.
And just to start on a clean slate, please power down your core, router, and devices, and unplug them for a few minutes. From there, go ahead and restart them and see if you’re issue persists.
Thanks Ulrich!