I had an update on my Watch 6 on December 15th and I noticed today it's not accurately reporting steps to milage aince then. I had 8,000 steps today, for example, and it's only showing it as 2.7 miles when normally 7,500 steps is around 3.3 miles for me. I've also noticed when calibrating my tredmill walks the last few days it's off drastically from my tredmill. Before the update they were always pretty close to exact. Yesterday I walked 3.3 miles on the tredmill at 7700 steps per my watch, my daily total was 10,272 steps and only amounted to 3.92 miles. That should have been closer to 5 miles. Not really sure what I can do to fix that, but hoping Samsung sees this and fixes it.
