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 s1.dkim.cosmored_mx.1cd.onsecureserver.net. is not the root of its zone.
Instead, try zone transfer on 1cd.onsecureserver.net .
Instead, try zone transfer on 1cd.onsecureserver.net .