spf.bytedance.com has no MX records.
Question and response
Question
dig spf.bytedance.com. MX
Answer
The response has no answer records.
Authority
bytedance.com. 600 SOA vip3.alidns.com. hostmaster.hichina.com. 2026010716 3600 1200 86400 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0