Autosave during cycling.

This is probably the problem my wife is having with hers as whenever we go out for a ride together it seems to cut out halfway through. I don't get this issue on my Fenix 5+ or Edge 830 so we have rely on my data.

Maybe band is loosing GPS connectivity because phone kills connect app for power saving? Turn off power management for Garmin Connect (Android)

I have a similar problem - when the autosave comes on and i am riding it then registers my sleeve as touching the screen!

It's not necessarily random: when this happens to me, it's detecting a double-tap touch on the screen (or several - one to turn the screen on, and one to end the workout), which can happen if wet fabric (e.g. glove cuffs, jersey sleeves) happens to bump the screen in a double-tap pattern. It happens most to me riding in winter, because the extra layers mean I'm not evaporating sweat as quickly, so my base layer tends to get more damp than in spring/summer/fall (also happens more when it rains in summer, as my rain jacket inevitably traps some sweat).

You can't really avoid this sort of problem entirely with capacitive touchscreen devices; you need some kind of physical button to turn the screen touch detection on and off to completely prevent it. Designers are still working out optimal ways to deal with wet touchscreens - it's become an increasing problem with phones as more phones have become waterproof (so people are trying to use them while wet). Capacitive touch sensors work by, in essence, detecting that the water in the tissues of your fingertip have displaced the air that was there, changing the capacitance of the capacitor that functions as the sensor, and they react just as well to water that isn't in a fingertip as water that is. One option would be to go back to resistive touch detection, but we moved away from screens using that in the first place because so many people had trouble using them (they're not as responsive, which means some people most of the time and most people some of the time have trouble getting them to respond as desired).

I suggest looking for a fitness tracker that has a physical screen on/off button (or a physical workout start/stop button) if this is a major concern for you, because other touchscreen-only devices are also likely to have issues with ghost touches while wet.

Oh, I minimize the problem by swiping to the alternative view with the clock during a workout - that requires a ghost double-tap, swipe, and then double-tap again (within the display timeout window) to inadvertently end the workout, which is a less likely combination than two double-taps, though I've still had it happen.