Apple watch unresponsive after swimming

Yesterday after swimming the touch screen on my watch stopped working. You can't enter the password, swipe up or down, putting my palm on the face doesn't turn it off and hard pressing doesn't activate the edit face option. The digital crown and side button function perfectly though and I can see the time on the face.

To try to fix it I have done the following ...

Rinsed it under luke warm water

Left it overnight on its charger

Force reset it many times

Checked software is latest (5.3)

Unpaired and re paired it to my phone.

It is still unresponsive.

It is an Apple watch series 2 and is 2 years old.

Any suggestions?