>> When running it doesn’t accurately measure the miles (by a margin of error of more than 20%).
Are you using connected GPS? Presumably not : in that case the tracker uses the stride length to compute the distance and hence if that number is wrong, also the distance estimate is wrong. The stride can be set manually to a fixed number (different for walking and running) or automatically based on height and weight. I recommend to walk a known distance, a few 100m will already do, count the steps, and then divide so you get the stride length, and use this value to set the manual input.
>> Sometimes counts steps I didn’t do and/or keeps the steps from one day to the next.
Pls be more clear EXACTLY what you mean, provide an example.
