[Users] cert issue

[lists at lazygranch.com]

This may not be a claws issue. Using letsencrypt, I set up a cert with
mail.example.com and example.com. I set up claws to use
mail.example.com.

This cert caused a problem with the website at example.com, so I got rid
of the mail.example.com subdomain. 

I changed the claws accounts to use example.com The cert
for mail.example.com has expired and I intend not to use it.
(letsencrypt is going to allow wildcard certs soon if not already, but
that is another story.) 

I would like claws to use the cert for example.com, but I keep getting
the message that mail.example.com has expired. How do I force claws to
use the top level domain cert (example.com).