_525c0181a9dc09713371bf8654662d2a.spf.dnssmarthost.net. IXFR zone transfer

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 _525c0181a9dc09713371bf8654662d2a.spf.dnssmarthost.net. is not the root of its zone.
Instead, try zone transfer on spf.dnssmarthost.net .