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 4761f6c8ae6d is not the root of its zone.
Instead, try zone transfer on 4761f6c8ae6d. .
Instead, try zone transfer on 4761f6c8ae6d. .