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 static-dsl-55.213-160-174.telecom.sk is not the root of its zone.
Instead, try zone transfer on 213-160-174.telecom.sk .
Instead, try zone transfer on 213-160-174.telecom.sk .