NEX 3N - Full battery - no response

[Watsonite]

 

I own a NEX-3N from 2015 wich I didn't use much when bought. It ended back in the box after a short while. Now, years later, when I want to use the camera again, it won't respond to anything. The batteries I have are fully charged and almost never used. Nevertheless, the camera does not respond to turning it on.

 

I have tried several internet solutions and resets, provided by Sony as well as by others but with no results.

At one try, the reset made the lense come to live for two seconds before turning dead again.

The camera has hardly been used and sat in the box for years now.
The camera hasn't been damaged nor been exposed to extreme conditions.

Anyone any idea on how to get this Sony back to life again?

Thanks!