It now says it cannot charge because it needs a proper Sony Ericsson Battery... it is and has always been... I tried 2 new batteries and same thing... different chargers... same thing... CAN ANYONE ADVISE PLEASE? I want to save my phone.
That device is known to have hardware issues, sometimes fatal. Unfortunately it may just be time to upgrade, or get another one of the same device on eBay or something. At this point your phone is a five-year-old model, so you could probably find the same one for under $10 online.