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 _64084c9686fbbbd02a08a3d5a20454c4.nxzthgqctm.acm-validations.aws is not the root of its zone.
Instead, try zone transfer on nxzthgqctm.acm-validations.aws .
Instead, try zone transfer on nxzthgqctm.acm-validations.aws .