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 it-pom-server.powered-by.c1vhosting.it is not the root of its zone.
Instead, try zone transfer on c1vhosting.it .
Instead, try zone transfer on c1vhosting.it .