Hi
The best thing to try at the moment is to try resetting the controller
Here’s a video on doing it
[link|https://m.youtube.com/watch?v=_RU8m0fsCds|https://m.youtube.com/watch?v=_RU8m0fsCds|new_window=true]
It could something stuck in the charging port but that’s unlikely due to its age
Apart from what has been mentioned previously it’s probably best to contact Sonys customer support and see if they can fix it under warranty as if you try and open it it will void the warranty
Hopefully this helps
Any questions please ask
Thanks:-)