Original post by: Augustine ,
Hi @star5281, based on your phone, I think that the battery has reached EOL (End of Life) I had a model similar and was showing the same issues. Most probably a replacement of new battery will resolve this issue. Take note on your iphone model carefully, eg. AXXXX You can find the guide from ifixit to dismantle it. I would suggest getting your battery replacement from ifixit, as they offers excellent replacement for the iphone battery.