How to import gpx files from a Mac to Edge 1050

1.

Just having a 1050 delivered, I had hoped to import some gpx files into the Edge from my Mac Studio running under Sonoma 14.5.

However the 1050 does not appear as an external volume. The Edge is also not recognized by Disk Utilty.

Rebooting the computer or using another Garmin branded USB-C cable did not help.

2.

So I tried to upload several gpx files through my Garmin Connect account, using Safari, but also this doesn't work.

Each time an error message appears.

Does anyone have a suggestion of another workaround?