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 40ho8s4kg3f8d1h5q6db6e79u4s1ptlf.sk.eserver.net is not the root of its zone.
Instead, try zone transfer on sk.eserver.net .
Instead, try zone transfer on sk.eserver.net .