When I take a break on a walk or hike, I would like to stop the activity and resume it when I want. But the Auto Save function only gives you one minute before it saves so I would like to be able to disable it.
Add my vote for this feature request. An alternative would be an explicit pause option in addition to the save, resume, and delete options: that would allow people who want to pause for longer than the auto-save timeout to do so without having to reset the timer every minute.
Do you still have the fit files from your vivosmart 4? Might be possible to repair the activity by connecting the files into 1 activity using some of the fit file tools available or post to this thread requesting assistance - How to repair a .fit file?
I understand that. Just offering you some assistance with this particular 100km activity that was ruined. For Garmin requests there is this site - Share Ideas. Or you could open a case with Garmin Support.