Apple Watch Series 6 wrist sensor not working after water immersion

I was washing up and the watch got wet.

The touchscreen works intermittently, but the wrist sensor doesn't seem to have activated since that day (it hasn't taken my heart rate since that day).

Is there anything that can be done?

I have force restarted it, I have even wiped it and started afresh. All of the things everyone says to do I have done.

I guess my question is, what next?

Thanks!

[Re-Titled by Moderator]