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 ns6.p200.dns.uk-gov-cardiff-1.oci.oraclegoviaas.uk is not the root of its zone.
Instead, try zone transfer on uk-gov-cardiff-1.oci.oraclegoviaas.uk .
Instead, try zone transfer on uk-gov-cardiff-1.oci.oraclegoviaas.uk .