S3 wont turn on or charge

[AC Question]

Hi
So last night my phone was working fine and i went and put it on charge
I came back to my phone and it was 50% charge
I took it off charge and as I was using it the battery starting to lose power quite quickly
I checked if anything was running in the background but nothing was
I then saw my battery was at 1% and as I went to charge it, the phone screen flickered 3 times and turned off
I have tried to charge it and even tried a new battery but the phone still wont charge
HELP!
I have a samsung galaxy s3

 

[B. Diddy]

Welcome to Android Central! Check the battery contacts on the inside of the phone--are they clean? When the battery is seated in its slot, is it snug or loose? Any recent drops or other trauma to the phone?

Plug the phone into a wall outlet and leave it there undisturbed for 10-12 hrs. Then try to start it again. You may also want to remove the SD card, in case it's become corrupted (which can contribute to battery drain).