diff --git a/pkg/mail/send_mail.go b/pkg/mail/send_mail.go
index 8be4dda4b..4e54ceccf 100644
--- a/pkg/mail/send_mail.go
+++ b/pkg/mail/send_mail.go
@@ -85,7 +85,7 @@ func getMessage(opts *Opts) *mail.Msg {
 	m.Subject(opts.Subject)
 
 	for _, h := range opts.Headers {
-		m.SetHeader(h.Field, h.Content)
+		m.SetGenHeader(h.Field, h.Content)
 	}
 
 	for name, content := range opts.Embeds {