spf.os-ns.com has no CNAME records.
Question and response
Question
dig spf.os-ns.com. NS
Answer
The response has no answer records.
Authority
os-ns.com. 3600 SOA n1.os-ns.com. hostmaster.os-ns.com. 2025042002 3600 3600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0