Here is a list of issued certificates crt.sh | thomsclan.com, the latest being 2025-01-30.
And these are the matching identities autodiscover.thomsclan.com, mail3.thomsclan.com, mail.thomsclan.com, and thomsclan.com for recent certificates. Assuming that is what you are wishing to renew and using the HTTP-01 challenge each one of them must have an IP Address (IPv4 and/or IPv6).
And here is what I see for DNS
