I cannot start a new round of golf as the watch ends its immediately on its own

Till today the S70 was acting great. But now, if I start a round, all preparation steps go as normal.

I press Golf on the watch, wait for GPS, watch searches for nearby courses, select a course, check to register score, select a tee, the first hole is shown but after 1 second the watch ends the round on its own. It looks as if the menu button is pressed, that icon is shown for a short moment nearby the red button, but I am not pressing any button.

The "round" is visible in the Garmin Golf App as an empty round. I can do this over and over again, with the same result. So I have a long list of empty rounds (easy to delete of course) in the Garmin app.

I have shut down the watch and started again, doesn't help.

I choose to skip GPS, doesn't help.

I choose not to keep scores, doesn't help.

Reset the watch, even that doesn't help.

Can anyone please help?