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 c-u-s-t-o-m-e-r--dynamic-186.235.83.6.brava.net.br is not the root of its zone.
Instead, try zone transfer on brava.net.br .
Instead, try zone transfer on brava.net.br .