Could not verify SSL certificate. Please check certificate installation for domain!

Hey all. I am getting this error from Zapier about my domain when Agile CRM tired to fire a zap:
Agile CRM: Could not verify SSL certificate. Please check certificate installation for domain!

The only thing I’ve changed recently is adding a CNAME to the domain to create a subdomain. The zap has been set up and working for at least 6 months.

Any ideas on fixing this?

What’s the hostname?