Navigation system failure in the 2015 Opel Insignia: experiences and solutions

Navigationssystem is not working

Hi guys, I have a problem with my 2015 Opel Insignia (gasoline engine, 84170 km). The sat nav no longer works, I suspect a screen failure. Have any of you ever had a problem like this? What was your experience with the garage? Unfortunately, I didn't have a good experience on my last visit. I am looking forward to your answers!

(Translated from German)