As I was editing my reply you post has been moved to one of the links I provided
There are so many possibilities and it may help if you explain not just what you have done but what you have done in regard to suggestions in the above posts.
Very often the cable or the USB port require more attention. Failing that see if you can find a fairphoneangel near you that can maybe provide a replacement bottom module or you can buy one to see if that helps.
