Apex domains cannot have CNAME records.
Question and response
Question
dig ip-162-19-89.eu. NS
Answer
ip-162-19-89.eu. 2 NS ns112.ovh.net.
ip-162-19-89.eu. 2 NS dns112.ovh.net.
Authority
The response has no authority records.
Additional
ns112.ovh.net. 5 A 5.135.80.109
dns112.ovh.net. 5 A 5.196.45.209
ns112.ovh.net. 5 AAAA 2001:41d0:b01:0:0:0:0:2
dns112.ovh.net. 5 AAAA 2001:41d0:d01:600:0:0:0:2
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0