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 0s40a1gva7nlrv8thfcmrvierbfum8ta.itfhosting.dk is not the root of its zone.
Instead, try zone transfer on itfhosting.dk .
Instead, try zone transfer on itfhosting.dk .