wohnungen.alstjohn.com has no NS records.
NS records for this zone are defined at alstjohn.com.
NS records for this zone are defined at alstjohn.com.
Question and response
Question
dig wohnungen.alstjohn.com. NS
Answer
The response has no answer records.
Authority
alstjohn.com. 3601 SOA dns1.registrar-servers.com. hostmaster.registrar-servers.com. 1772789860 43200 3600 604800 3601
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0