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 3t8tr560l3dl5rkkkh9r2ab6135bct8c.dbk.dk is not the root of its zone.
Instead, try zone transfer on dbk.dk .
Instead, try zone transfer on dbk.dk .