mta005.uk.t1cloud.com has no CNAME records.
Question and response
Question
dig mta005.uk.t1cloud.com. NS
Answer
The response has no answer records.
Authority
uk.t1cloud.com. 880 SOA ns-1613.awsdns-09.co.uk. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0