Even if you have a dead phone as you think , there is a chance to revive it . Just make sure to act quickly
the longer the water inside your phone , the greater the chance of destroying it ...remember that .
Consumers usually return defective products , but the warranty of your phone does not include water damage
so follow this steps :
Step 1: Don't turn on your phone after the water has Penetrated into its parts
Step 2: Remove the battery
Step 3: Remove the SIM card
Step 4: Dry your phone :
Dry your phone and do it quickly . If you leave the moisture to evaporate normally, your machine may be exposed to corrosion damage in its interior parts. Instead, blow or suck the water out. But do not use the hair dryer as its temperature may burn the internal parts of your phone. Instead of the dryer, use a vial of compressed air. The idea is to use the air to attract or push moisture out of the phone .
Step 5: Use a Desiccant :
The best choices you have are uncooked rice . Leave the phone alone (and its uncluttered battery) inside a bowl of rice for one night and congratulation you can now switched the phone on .
source : https://www.popularmechanics.com/technology/gadgets/how-to/a3419/dry-out-your-cell-phone/