In the last week or so whenever I do exercise it intermittently adds the activity calories on the daily activity heart.
So for example this morning I did some exercise and the calories were correctly added and took it up to 340 calories burned. Then at lunch time I went for a walk however when I finished walk and it saved my overall activity calories had actually dropped by about 20!
This has happened a few times now which obviously affects trying to close all three rings of the heart.
I've restarted the watch but that hasn't helped either