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 6c0a8f9b33e5bcf8ad1fb39cf9a6532e.1c138d6afa1ae1e412c75e884103b512.comodoca.com is not the root of its zone.
Instead, try zone transfer on comodoca.com .
Instead, try zone transfer on comodoca.com .