Perhaps you could email them and say you had ordered the certificate. When it arrived there was a reference to the Register of Corrected Entries, but they had not sent this with the certificate, would it be possible for them to send it now?
If it were an earlier certificate, available to see on-line, and there was a reference to an entry in the RCE, there is a link that allows you to see it at no extra cost, if you have paid to see the actual certificate.
The RCE might explain the reason for the change.