_spf.sap.com has no MX records.
Question and response
Question
dig _spf.sap.com. MX
Answer
The response has no answer records.
Authority
_spf.sap.com. 259200 SOA ns1.sap.net. dns.sap-ag.de. 2019050733 3598 1800 1814400 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0