mercury.ubs.com has no MX records.
Question and response
Question
dig mercury.ubs.com. MX
Answer
The response has no answer records.
Authority
ubs.com. 300 SOA cnsi-rzud-6601.core.ubs.net. ncc-internet.ubs.com. 2009381244 900 90 604800 300
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0