Nextbox : Linux autosync daemon fails today?

Without having changed setup, I see this morning that the little Nextcloud daemon on my Debian Linux machine announces “network is not answering” when trying to connect/sync my local folder with my server at … .
Html connection works flawlessly (I even dared to update tne terrifying Mail app :wink: ), the daemon does connect with an old, externally hosted nextcloud instance, and rebooting the Nextbox doesn’t help. Is it an issue with .dedyn?
[edit : it works now, two hours later. I’ll delete this post if this continues. Still, I can’t understand what happened here…]