*.conventioncalendar.com has no CNAME records.
Question and response
Question
dig *.conventioncalendar.com. NS
Answer
The response has no answer records.
Authority
conventioncalendar.com. 10726 SOA dns1.swiftrfp.net. admin.swiftrfp.net. 2023011256 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0