I have the same problem. I bought the Vivoactive 3 just today. But now, if this is really still an open problem, it goes right back into the box and back to the vendor. Can't be true, can it? Please tell me that there is an easy and convenient way to correct for badly recorded intervals, just delete them or ANYTHING, please!
Well, I saw someone delete intervals from a pool swim record with only so much as a swipe to the left or right. I mean: How hard can it be? It is basically to delete a row from a table, then recalc the table, nothing more, nothing less. How hard is that? Any intern should be able to get that done. It can't be that Garmin hasn't figures out a way to do this, can it? If the Samsung has the same problem, I know that it's not an alternative for me either...
Just got some responses from helpful support people. It actually works and you can edit the data. It is a bit cumbersome, but it does allow at least some degree of editing the data via the Garmin Connect Web tool and then exporting, editing, downloading and re-importing into the Garmin Connect Web tool again. The details are here: https://forums.garmin.com/apps-software/mobile-apps-web/f/garmin-connect-mobile-andriod/207320/is-there-a-way-to-delete-or-edit-individual-swimming-intervals-in-any-garmin-app-many-thanks