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 52.ip-91-134-141.eu is not the root of its zone.
Instead, try zone transfer on ip-91-134-141.eu .
Instead, try zone transfer on ip-91-134-141.eu .