rnd.businesspractical.de.com has no CNAME records.
Question and response
Question
dig rnd.businesspractical.de.com. NS
Answer
The response has no answer records.
Authority
businesspractical.de.com. 1502 SOA carlos.ns.cloudflare.com. dns.cloudflare.com. 2397267274 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0