Screen unlocks accidentally too often when wearing long sleeves.

Could you try locking the touchscreen? Hold A, select lock icon.

Of course if lock manually or set auto lock touchscreen accidental unlocking is not happening.

I remember the similar issue was with Venu when it was released but then a few months later it was an update that fix it. I hope this issue with Venu 3 will be fixed very soon.

It could be that Garmin is aware of this and they're planning an update. I would contact Garmin Support to be sure.

My venu3 is also right swiping way too, so I disabled it.

What I did instead is changing the middle button press shortcut to App and move all my most frequent apps to the top of list for quick access.

This works out better for me because it reduces 1 tap and less random right swipes

I'm wearing my Venu 3 in the shower and it will very easily unlocks screen and do an unexpected changes on the screen. Now I'm using auto lock screen all the time! It is inconvenient but safe. I hope the fix will come soon.

Same here with the shower issues. I have to lock the screen because it will go wild during a shower.

Not noticing it as much at different times, but there is the occasional time that it started doing something without my input.

Welcome to the fantastic world of amoled touchscreens

Same here. 

I would like a setting to force the screen to stay off until I press one of the buttons.

My watch from another manufacturer could do this. That functionality extended the battery life

It seems that everybody are complaining about the Venu3 touchscreen.. Plenty of thread on this subject..

Lock screen doesn't help as the screen it is still on very often as anything that touch it, will turn it on...

As it stands, the Venu3 it is unusable when wearing long sleeve, when in bed as sleep or in the shower...

Garmin is aware of this issue, so hopefully, a firmware fix or a recall on this product is not far away...