Cant charge a Series 7000 IWatch

No matter what I seem to do my old Series One IWatch will not accept charge. When connected to the charger I am getting the small green charge sign top left and a picture of what I guess is a grey coloured charging cord neatly folded down the screen. The watch gets quite hot but no charge seems to be going in as it will not start. I have looked at everything written in various forums to either soft or hard restart etc. The watch will not restart under any conditions I've tried. The watch was only used for approx 1 year and purchased just before the Series 2 arrived