diff --git a/boltcard.service b/boltcard.service
index 42a2ef1..bf32ab6 100644
--- a/boltcard.service
+++ b/boltcard.service
@@ -25,8 +25,9 @@ Environment="DB_USER=cardapp"
 Environment="DB_PASSWORD=database_password"
 Environment="DB_NAME=card_db"
 
-# HOST_DOMAIN is the URL base prefix for the lnurlw calls
+# HOST_ values are for https calls
 Environment="HOST_DOMAIN=card.yourdomain.com"
+Environment="HOST_PORT=9000"
 
 # MIN_WITHDRAW_SATS & MAX_WITHDRAW_SATS set the values for the lnurlw response
 Environment="MIN_WITHDRAW_SATS=1"