Have you exposed the device to physical or liquid damages?
I would recommend taking the device to a local ubreakifix.
You can locate the nearest location by visiting this link: www.ubreakifix.com/locations
Hope this message finds you well!
Why would you ever do this? What would make you want to test the water resistance of your expensive phone? Are you going to test the screen by dropping it too? Come on man.
What I would recommend trying is turning your phone off and setting it charging port down into a bag of rice. Do not shove any rice into the charging port (don't ever put anything put a charger into the charging port)
Once you have let your phone sit for at least 12 hours (do it overnight so you don't need your phone) use compressed air to clean your phone very well. Then place your phone (while still turned off) next to a tv that is on.
After you do this for at least a few hours turn your phone on and see what it says.
Just for the record the water resistance on all smart phones is tested in fresh water only. Not sink water, not salt water, not pool water, not any water but absolute fresh water. So remember that the next time you decide to test out the water resistance of your phone.
Did you even read their original post or any of the responses? They are having an issue immediately after testing their phone in water.
Also the water 'resistance' is only for fresh water. Not salt, sink, ocean, lake, river, or any other water that isn't fresh water. So they are not really 'resistant'. No phone is.