ur.ntp.srv is not a real NTP server but looks more like a request to insert the domain of a NTP server of your choice. So you probably changed your configuration following some tutorial.In Arch Linux the default systemd-timesyncd fallback server should just work so it's not necessary to change /etc/systemd/timesyncd.conf.
You can check with pacman -Qii systemd if you have modified the file. And if so you can compare the unmodified version by using the following command:
tar xOf /var/cache/pacman/pkg/systemd-$(pacman -Q systemd | awk '{print $2}')-x86_64.pkg.tar.zst etc/systemd/timesyncd.conf | diff /etc/systemd/timesyncd.conf -After fixing the NTP server configuration you can enable systemd-timesyncd with sudo timedatectl set-ntp true (alternatively you can enable ntpd)
