Changing HELO and RDNS

[bgholdsworth]

How does one change the DA.direct hostnames on the email server side? It is has been changed to DA.domain.tld on all other aspects of the server

For instance:

helo=server-xx-xx-xx-xxx.da.direct; pr=C

Received: from server-xx-xx-xx-xxx.da.direct (xx.xx.xx.xx) by

by server-xx-xx-xx-xxx.da.direct with esmtpsa  (TLS1.3) tls TLS_AES_256_GCM_SHA384

Thanks in advance