diff --git a/migration/20220915101901_initialize.tx.up.sql b/migration/20220915101901_initialize.tx.up.sql
index 1474c6e..cd958f2 100644
--- a/migration/20220915101901_initialize.tx.up.sql
+++ b/migration/20220915101901_initialize.tx.up.sql
@@ -35,7 +35,7 @@ create table if not exists user_detail (
 
 create table if not exists user_charge (
     created_at timestamptz not null,
-    seq bigint not null primary key,
+    seq bigserial not null primary key,
     user_id varchar(120) not null,
     fee numeric(12,2),
     discount numeric(5,4),