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Is it safe to assume that it's a 2013 version?
Did you happen to drop it while it was plugged in? Or do anything else that may have bent/damaged the pins in the micro-USB port?
You could examine the micro-USB port with a magnifying glass to see if anything looks out of whack.
Other than that if you've tried different USB cables and chargers I'd have to assume that there's something wrong with the battery.