I just recently (a month or two ago) purchased a VivoSmart 4 and I'm also seeing this issue. Looks like this thread is now 2 years old? How has this not yet been fixed???
I just started getting this issue on my Fenix 5+ about 3-4 weeks ago. All non-GPS activities seem to upload to Garmin Connect as being done in the Central Time zone, but I'm in the Mountain Time zone. The time on the watch shows as correct. I'm going to test out uploading through WiFi next time instead of through Connect Mobile and see if that changes this behavior in any way.
Same problem with my fenix 5x plus!
The funny thing is that I can't even change the time manually within the app afterwards
It just allows me to to pick a different time up to three hours in the past but not after the supposed activity.
It really is driving me nuts.
3 years and counting with no fix, eh Garmin? I just started noticing this issue. I can pinpoint it exactly to Daylight Savings Time. Prior to March 8th this year, all my non-GPS activities recorded correctly in Mountain Time. After the 8th, they're all in Central Time. Maybe that'll give the devs someplace to start looking?
And the Upload Time Zone is set correctly in your User Profile settings? If yes, and the uploaded times are still wrongly set in activities, simply select a time zone an hour shifted from yours. Maybe not perfect, but still better than waiting for the devs to start looking.
It's now 2023 and this is still happening. I noticed it for the 1st time today since moving from Fitbit Charge 5 to a Garmin FR245 Music