Google quickly led me to https://github.com/rpm-software-management/libdnf/blob/master/libdnf/dnf-repo.cpp#L1690
And then I notice the media in your repo list. That will come from a file in /etc/yum.repos.d - I’d delete it unless you’re explicitly trying to load RPMs from a CDROM/DVD. If you are…hm, probably a bug in libdnf.