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 mta-aws-211-91-250-13.mailtarget.co is not the root of its zone.
Instead, try zone transfer on mailtarget.co .
Instead, try zone transfer on mailtarget.co .