When I ran
apt-get update, I got the following warning message:
N: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Version' value from '10.3' to '10.4'
There is a new Debian version. You can upgrade from version 10.3 to 10.4. I did upgrade using the following command.
apt-get -y dist-upgrade