GAP is too much faster for all of my runs

did you try usinbg the list view and do a filter for Runs?

I am encountering the same problem and my settings for Elevation Correction have always been “No”, and GAP Model from Strava run.
My run is not flat, it contains laps on a hill. Runalyse and Suunto App, or the Suunto watch itself during the activity, show a totally different GAP (for each individual lap, and obviously as an average) than intervals.