Apex domains cannot have CNAME records.
Question and response
Question
dig sng.ibb.ubs.com. NS
Answer
sng.ibb.ubs.com. 1 NS mercury.ubs.com.
sng.ibb.ubs.com. 1 NS uranus.ubs.com.
sng.ibb.ubs.com. 1 NS jupiter.ubs.com.
sng.ibb.ubs.com. 1 NS neptune.ubs.com.
Authority
The response has no authority records.
Additional
uranus.ubs.com. 1 A 156.115.14.70
jupiter.ubs.com. 1 A 161.239.244.75
mercury.ubs.com. 1 A 155.145.206.75
neptune.ubs.com. 1 A 147.60.6.75
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0