You could try battery replacement next. Or connect iPhone to computer let it charge for a while, then with iTunes open. Hold both home and power buttons until iTunes recognizes iPhone in Recovery Mode. This usually takes about 20 seconds of holding both buttons. Restore the Firmware. If still problem, then try replacement of the battery.
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Definitely dry it completely as David recommends. You could try battery replacement next. Or connect iPhone to computer let it charge for a while, then with iTunes open. Hold both home and power buttons until iTunes recognizes iPhone in Recovery Mode. This usually takes about 20 seconds of holding both buttons. Restore the Firmware. If still problem, then try replacement of the battery.
You could try battery replacement next. Or connect iPhone to computer let it charge for a while, then with iTunes open. Hold both home and power buttons until iTunes recognizes iPhone in Recovery Mode. This usually takes about 20 seconds of holding both buttons. Restore the Firmware. If still problem, then try replacement of the battery.