'New' resting heart rate - should I reset my Vivosmart 5?

I've recently had a valve replacement after years of right ventricle dysfunction. As a result I have come off one of my heart failure meds that was keeping my heart rate low. So my resting heart rate is now about 10bpm higher and my Garmin assumes it's because I am stressed all the time.

I came home from hospital 3 weeks ago and while my 'stress' level is slowly creeping down I never make it to the 'rest' zone. My body battery never gets above 26 and my sleep scores never get above 49. I'm still resting for a lot of the day and not doing anything strenuous other than a couple of walks each day. I've had my Garmin for about 18 months and it seemed to fairly accurately represent my energy levels, stress levels and sleep quality before my surgery. Will it ever recalibrate to my new normal heart rate, or should I reset it? At this stage it's a glorified step counter, whereas before it was able to pick up small changes due to hormone fluctuations and alert me when I was starting to get sick.