What is Reserved Balance?
Reserved balance is funds Openprovider blocks in your account when there is a pending order, for example a pending transfer or an opened SSL certificate order.
As soon as the transaction is finished, the amount will be deducted from the normal balance and the amount reserved will be 0. If a transaction fails, the amount will remain reserved until it is credited, for example by removing the failed domain from your account.
You can see the transactions that are booking balance from Account > Financial > Reserved Balance.