If you have not turned the phone on, there is two methods to salvaging the phone.
a) get a zip lock bag and put your phone into it and fill it to the brim with uncooked rice.
b) best results, you will have to remove the battery and place the device without the battery into a zip lock bag then fill it up with rice.
In either scenario - leave in the bag - for one to two months as it has pretty much dunked into water. The rice should draw out the moisture and I would also recommend leaving the rice stuff zip lock back in a very dry and cool place so no other moisture would be absorbed.
However your milage will very as it entirely dependent on how many times you may have tried to turn the phone off / on and/or attempts at charging it.
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