Apple Watch Ultra 3: Treadmill distance sync issue in Health

I wear my Apple Watch Ultra 3 and sync it with the Matrix treadmill. Treadmill and watch show 4 miles. Health app only shows 3.7 miles. Why sync to the treadmill if the health app doesn’t sync with the data? I use this date for my health provider saying I do 4 miles on the treadmill, which I do. Not syncing correctly I am very annoyed