Import from Polar Flow / Beat

I am trying to use Intervals.icu with my students. They are tracking their training in Polar Beat / Flow.

They setup the integration.

It seems however, like activities are imported double:

But with a little different time and load (probably something to do with moving time).

As I understand it the import will happen on all new activities when it is setup.

Did we setup something incorrectly since they seem to import twice?

Are they also connected to Strava?
Open some of the activities and check the source.

Both seems to be imported from Polar:

Example:

Does Polar also show both?