Thank you for your reply. Actually, I already added the following records in the existing DNS provider, and all are checked fine with propogation tool you attached, but not helping…
_acme-challenge.zhuogang.online (CNAME record) for DCV Delegation
cloudflare-verify.zhuogang.online (TXT record with blank string) for verification
I doubt that should be a blank string. Is this really the correct screenshot? If so, open a support ticket and ask them to clarify, as the value in question is seemingly not displayed.