If it got submerged in water, anything could've happened inside the phone that damaged it due to the water. Four hours drying time likely wasn't long enough either, and plugging it in could've caused additional damage. My suggestion is take it to a repair shop, let them know what happened, and have them fully diagnose any problems.
Depending on the age of the phone and the fact that corrosion may set in that causes more problems later on the parts not replaced this time, it may not be worth it to fix it. In which case, you'd be better off replacing it all together.
12-06-2018 10:47 PM