Iphone 8 Plus won't record or play videos

I have an iPhone 8 Plus which does not record videos from the photos app. Also it cannot play any videos that have been recorded with the iphone itself a couple of weeks ago.

I also cannot play any videos from e.g. youtube or any other video platform.

In youtube (no matter from safari or the yt app) I tap on a video and I get to see the videos thumbnail but the video does not start to play.

Another weird behaviour is that starting the photos app takes a couple of seconds. It immediately starts but the screen stays black for some seconds. Then I can take a photo. For live photos it the same as for videos, it takes the picture but the video / live part is not being recorded.

Switching to record a video shows the live view, then clicking on record changes the record button to indicate it's recording, but the record timer does not start and nothing is being recorded.

I resetted the iphone multiple times.

Via icloud and also wired from a macbook. Currently I upgraded to iOS 16.

Everything worked as it should but from one day to another the weird behaviour started.

Today I finally went to an apple retail store to diagnose the iphone. The diagnose stated that there's no hardware issue.

The guy told me that he cannot do anything and that I can replace it for a couple hundreds euros.

So basically it's electronic waste ...

Does anyone ever have experienced such a behaviour and is there a solution to the problem?

@apple interested to debug some weird hardware / software issues? 🙃

Thank you very much!