diff --git a/bgpwtf/invoice/model.go b/bgpwtf/invoice/model.go
index 1fb89b9..fcf4aba 100644
--- a/bgpwtf/invoice/model.go
+++ b/bgpwtf/invoice/model.go
@@ -75,11 +75,11 @@
 			invoice_id, final_uid, sealed_time
 		) values (
 			?,
-			( select printf("%04d", ifnull( (select final_uid as v from invoice_seal order by final_uid desc limit 1), 19000) + 1 )),
+			( select printf("%04d", ifnull( (select final_uid as v from invoice_seal order by final_uid desc limit 1), 20000) + 1 )),
 			?
 		)
-
 	`
+
 	sealTime := time.Now()
 	if useProformaTime {
 		sealTime = time.Unix(0, invoice.Date)