diff --git a/constant.go b/constant.go
index 1a33118..0a19f88 100644
--- a/constant.go
+++ b/constant.go
@@ -22,8 +22,10 @@ var SellyService = struct {
 	User       string
 	HelpCenter string
 	Order      string
+	Withdrawal string
 }{
 	User:       "user",
 	HelpCenter: "help_center",
 	Order:      "order",
+	Withdrawal: "withdrawal",
 }