Customers not receiving purchase confirmation emails

Site URL: https://www.eurocastbrands.com

Just recently my customers stopped receiving automated purchase and shipping emails that my site used to send. I checked my Commerce>Notification settings and everything seems the same ... test emails came to me. I asked customers who called (because they were looking for their confirmations) to check their spam folders and they said they found nothing. Any thoughts?

I have attached a screen capture showing my order confirmation notification settings.

Thank you in advance for any time and help any of your can provide.

Did you ever figure out what was going on with your issue? I have been having the same problem and keep having to resend the Order Confirmations to customers. Thanks.