fixed error code in mailalias function

func/domain.sh

@@ -506,12 +506,12 @@ is_mail_domain_new() {
 is_mail_new() {
     check_acc=$(grep "ACCOUNT='$1'" $USER_DATA/mail/$domain.conf)
     if [ ! -z "$check_acc" ]; then
-        check_result $E_EXIST "mail account $1 is already exists"
+        check_result $E_EXISTS "mail account $1 is already exists"
     fi
     check_als=$(awk -F "ALIAS='" '{print $2}' $USER_DATA/mail/$domain.conf )
     check_als=$(echo "$check_als" | cut -f 1 -d "'" | grep -w $1)
     if [ ! -z "$check_als" ]; then
-        check_result $E_EXIST "mail alias $1 is already exists"
+        check_result $E_EXISTS "mail alias $1 is already exists"
     fi
 }