Unable to edit domain

The domains page at http://.../postorius/domains has a list of the domains that exist along with edit and delete buttons for each listed domain. Adding a new domain goes to http://.../postorius/domains/new/ which has input boxes for Mail Host and Description (and with !186 (merged) Alias Domain) and a dropdown list for Web Host. This all works well as does deleting a domain.

The issue is editing a domain goes to http://.../postorius/domains/<domain_name>/ this form is similar to the new form, but there is no Mail Host input box, just a header that says Edit domain <domain_name>, but the validations for this form require a value for mail_host which would be the Mail Host input, so the form is never valid.

I have looked through the code and both the new and edit forms are produced by forms.domain_forms.DomainForm() called by views.domain.domain_new()andviews.domain.domain_edit()respectively and the corresponding templates are atpostorius/templates/postorius/domain/new.htmlandpostorius/templates/postorius/domain/edit.htmlrespectively. I can't see where the input box forMail Host` is dropped so I'm lost when it comes to fixing this.