Apex domains cannot have CNAME records.
Question and response
Question
dig telekom.com. NS
Answer
telekom.com. 5 NS dns2.telekom.de.
telekom.com. 5 NS dns1.telekom.de.
telekom.com. 5 NS ns1.telekom.net.
telekom.com. 5 NS pns.dtag.de.
Authority
The response has no authority records.
Additional
ns1.telekom.net. 5 A 212.185.24.65
pns.dtag.de. 5 A 194.25.0.125
dns1.telekom.de. 5 A 194.25.225.19
dns2.telekom.de. 5 A 194.25.225.3
ns1.telekom.net. 5 AAAA 2003:180:a:1000:0:0:0:53
pns.dtag.de. 5 AAAA 2003:40:8000:0:0:0:0:100
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0