Email sometimes fail to receive the Confirmed BCC letters "Order status notifica

Hi,

First, please check the menu Customers>Emails history.
There search for the emails that you didn't receive.
If you see it and it has the correct bcc, then the issue is not with HikaShop or its settings because that means that the email was properly given to the email server of your hosting to be sent with the bcc.
So in that case, the thing to do would be to check with your hosting (you can give them a screenshot of the details of the email) and they can look for it in the logs of their email server.
It's highly likely to be a spam issue either because the email was rejected by their email server, or because the receiver email server rejected it. And in that case, you can test the email with something like www.mail-tester.com/