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 dns006-ext-vip-chiadc01-rprxy1-19.chi.ford.com is not the root of its zone.
Instead, try zone transfer on chi.ford.com .
Instead, try zone transfer on chi.ford.com .