Download failed. Check back later for updates.

I have a new Garmin Edge 840 (a few months old) and updated to 26.18. When I now check for update over wifi the device always comes back with the error "Download failed. Check back later for updates."

I also notice that the Garmin Connect app on my phone is constantly trying to send some software update to the device while the Connect web says " Software is up to date — Version 26.18 ".

What gives and how do I resolve this?