Apple Watch strap causing skin irritation and rash

I have had my Apple Watch SE generation 2 for 3 years and have never had any problems with it. About 3 months ago I noticed two red dots (almost like bug bites) that turned into a red circle under where the sensor makes contact with your skin. I decided to switch my watch to my other wrist and after a couple of weeks the same thing happened. I decided to buy a watch case thinking this might help (the sensor is not covered) and the red area has come back and is more irritated than it was the first time around. Is there anything Apple can do to test the watch to see if it is causing a burn or will they help you exchange for a watch with a different metal? Any other suggestions on how to fix this problem? I am a nurse who needs a watch for work and I would hate to have to get rid of my Apple Watch after that being the only watch I’ve used for the past 10 years.

[Re-Titled by Moderator]