am3-v-gcdn-mail-vip.p.gc.onl IXFR zone transfer

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 am3-v-gcdn-mail-vip.p.gc.onl is not the root of its zone.
Instead, try zone transfer on p.gc.onl .