Nike Sportswatch+ GPS by TomTom WM0072, Lime Green/Black - Needs Repair

Good condition! The watch is in excellent cosmetic condition, with nearly no signs of wear. The watch currently powers on as normal only when it is plugged into the charger (it has a built-in USB charger in the band). The screen shows full battery. However, once removed from power, the watch turns off. I am guessing it needs a replacement battery. The watch was working perfectly for all functions before this issue began.