I just bought a brand new Forerunner 255. I've tracked 5 activities so far, and in 2 of them, there was a significant deviation from the actual path. The actual GPS route seems to be somewhat accurate, but the overlay on the map in Garmin Connect is way off.
In the first activity it was off pretty much the entire route, expect for the very end:
https://connect.garmin.com/modern/activity/9443162832
And in the second it's even weirder. You can see that in the first half the lines corelate very well with the road above, even though the overlay is wrong. But the second half of the walk actually seems to be pretty spot on. Starting and ending points were the same. And for this one I actually used dual band all systems tracking.
https://connect.garmin.com/modern/activity/9448940345
The other three activities I've tracked are spot on.
Any idea how to fix this? Is it a software issue or a hardware problem? I've connected the watch to Garmin Express and there are no new updates available, so it seems I have the latest version.