Forerunner 265 is suddenly saying that I have high stress during sleep...even during deep sleep

I have been wearing my new Garmin Forerunner 265 for about 7 weeks.  It has been mostly fine so far (the blue triangle was a brief problem).  Until three days ago, my stress levels during sleep have been low and all seemed well and good.  However, three days ago, my stress scores while sleeping have skyrocketed and suggest that I was highly stressed even during deep sleep.  I have not made any major changes to my sleep routine.  I also eat fairly healthily, exercise and don't drink.  

Due to the fact that my baseline was low, I am thinking this might be a technical glitch.  I am wearing the watch correctly.

I had a Garmin Instinct for years and never had any issues.  It was a less advanced watch (plain old digital face...nothing fancy), so maybe there were fwer things to go wrong.

Has anyone experienced this same issue?  Any suggestions for a fix are appreciated!