Changes since SOA version
IXFR is a zone transfer request that returns changes since a specific SOA version. Enter the SOA version to request changes since then.
Not an apex domain
The domain v5nqf40g9cdfj5afs00slt6e1sn4dgn8.dnsfactory.dk is not the root of its zone.
Instead, try zone transfer on dnsfactory.dk .
Instead, try zone transfer on dnsfactory.dk .