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 ktn3pgorbin0hsp9uv90ef2gq3jl4nj4.dbk.dk is not the root of its zone.
Instead, try zone transfer on dbk.dk .
Instead, try zone transfer on dbk.dk .