When you installed your Debian 10 server by using one of the pre-releases, then you will get the following error message now that Debian 10 (Buster) has been released.
N: Repository 'http://security.debian.org/debian-security buster/updates InRelease' changed its 'Version' value from '' to '10' E: Repository 'http://security.debian.org/debian-security buster/updates InRelease' changed its 'Suite' value from 'testing' to 'stable' N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details. N: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Version' value from '' to '10.0' E: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Suite' value from 'testing' to 'stable' N: This must be accepted explicitly before updates for this repository can be applied. See apt-secure(8) manpage for details.
To switch your system to the stable branch and get rid of the above error, run this command:
apt-get --allow-releaseinfo-change update
