My face id is stopped due to rain water

It can occur that you will receive the following message on your iPhone or iPad Pro : " A problem was detected with the true depth camera, FaceID is disabled"

When you're getting this error message, Make sure that you're iPhone or iPad Pro is running the latest version of iOS or iPadOS. If your device is running the latest iOS or iPadOS and you're still getting this message and FaceID is not working:  contact Apple Support to get your device serviced.

Disabled Face ID alert on your device

if nothing works as per the instruction given in this link --> If an alert says Face ID has been disabled on your iPhone or iPad Pro

If you still need help, reset Face ID, then set it up again. Go to Settings > Face ID &Passcode and tap Reset Face ID. Then tap Set up Face ID to set it up again.

If Face ID isn't working on your iPhone or iPad Pro - Apple ...

With iPhone 12 models and later using iOS 15.2 and later, you can go to Settings > General > About to see the parts and service history of your iPhone and you can see if the camera has been replaced. If the repair was done using genuine Apple parts and processes, you will see "Genuine Apple Part" next to Camera.