MacBook Pro 15" suddenly shutdown, wont turn back on.

Hi all, yesterday i was working with my laptop while it was charging. i get up to move and unplug the power and a couple seconds later the entire machine suddenly dies.

for the last couple weeks the battery indicator has been saying off and on that it may need servicing so that may have something to do with it? i plug it back into power straight away and the light comes on. the battery indicator on the side was on 3 dots with the 4th flashing. left it charging for a while to try again later. the battery is now full and still has no life but notably it was a little warm. no where near hot. just like warm as if it had been running.

i have read through multiple other forums and tried to find a fix to no avail!. the only sign of life ive had was an SMC reset. all that happened was the light on the charger went green for a couple seconds then orange again with no other signs of life....

im really stumped on what the issue is so any ideas would be greatly appreciated!

thanks