diff --git a/src/registrar/utility/csv_export.py b/src/registrar/utility/csv_export.py
index f82fcbc99..d53d3ec1d 100644
--- a/src/registrar/utility/csv_export.py
+++ b/src/registrar/utility/csv_export.py
@@ -373,7 +373,7 @@ class DomainExport(BaseExport):
             domain_type = f"{human_readable_domain_org_type} - {human_readable_domain_federal_type}"
 
         security_contact_email = model.get("security_contact_email")
-        invalid_emails = {DefaultEmail.LEGACY_DEFAULT, DefaultEmail.PUBLIC_CONTACT_DEFAULT}
+        invalid_emails = [DefaultEmail.LEGACY_DEFAULT, DefaultEmail.PUBLIC_CONTACT_DEFAULT]
         if (
             not security_contact_email
             or not isinstance(security_contact_email, str)