MacOS Ventura (13.0), Nextcloud 3.6.4 "Host not found"

Dear Support,

I use Nextcloud on my old computer. I’m trying to use it on my new computer too, but I’m getting this error. What am I doing wrong?
Server address: https://saco.csic.es/remote.php/dav/files/USERNAME
Failed to connect to Nextcloud at: https://saco.csic.es/remote.php/dav/files/USERNAME
Host saco.csic.es not found

Thank you very much!
Cheers,
Amália