Sound doesn't work on Medion Notebook (Windows 10), why?

I don't really have a clue about notebooks and PCs in general and before that the sound was still working but now it says that I have not installed an audio output device. Why?

Go to where you bought this high quality device. Because a reputable dealer will be able to help you with any questions.

if I have any questions about a good wine or a high-quality roast, I speak to my dealer.

if there are problems with the brakes a year after buying my bike, i ask the bike dealer.

However, if I buy a sat nav from Aldi in the autumn offer just because they are selling the item for 19.95, then a year later I can't expect any support for upgrading to the Europe maps from the employee who gives the soup bags.

just like I'm an expert in my job…