Apex domains cannot have CNAME records.
Question and response
Question
dig szxlhwh.com. NS
Answer
szxlhwh.com. 5 NS ns-2045.awsdns-63.co.uk.
szxlhwh.com. 5 NS ns-275.awsdns-34.com.
szxlhwh.com. 5 NS ns-803.awsdns-36.net.
szxlhwh.com. 5 NS ns-1520.awsdns-62.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0