fix: add Date header for email

common/email.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/smtp"
 	"strings"
+	"time"
 )
 
 func SendEmail(subject string, receiver string, content string) error {
@@ -16,8 +17,9 @@ func SendEmail(subject string, receiver string, content string) error {
 	mail := []byte(fmt.Sprintf("To: %s\r\n"+
 		"From: %s<%s>\r\n"+
 		"Subject: %s\r\n"+
+		"Date: %s\r\n"+
 		"Content-Type: text/html; charset=UTF-8\r\n\r\n%s\r\n",
-		receiver, SystemName, SMTPFrom, encodedSubject, content))
+		receiver, SystemName, SMTPFrom, encodedSubject, time.Now().Format(time.RFC1123Z), content))
 	auth := smtp.PlainAuth("", SMTPAccount, SMTPToken, SMTPServer)
 	addr := fmt.Sprintf("%s:%d", SMTPServer, SMTPPort)
 	to := strings.Split(receiver, ";")