211.170.234.73.
Question and response
Question
dig spam1.tosspayments.com. PTR
Answer
spam1.tosspayments.com. 300 PTR 211.170.234.73.
Authority
tosspayments.com. 172800 NS ns-1420.awsdns-49.org.
tosspayments.com. 172800 NS ns-1909.awsdns-46.co.uk.
tosspayments.com. 172800 NS ns-216.awsdns-27.com.
tosspayments.com. 172800 NS ns-826.awsdns-39.net.
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0