在关闭事务时，Oracle DB Link不会更新数据库

I have some insert operations under the database "A". Next, I have an operation with the database "A" which connect with the database "B" using Oracle DB Link to update into the second one. When the method execution finish, all the operations over the database "A" are persisted, but the operation over the database "B" doesn't exist.I have some insert operations under the databas