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 16h1r36p2aejn642jv82k5u8tpgmi21n.comtecint.dk is not the root of its zone.
Instead, try zone transfer on comtecint.dk .
Instead, try zone transfer on comtecint.dk .