In your store's Admin area, go to the Sales > Customers > Edit Customer
You can enhance the interaction with your Customers by adding store credit or refunding Customers by store credit. After that, customers can use the store credit to make purchases on your store.
Transactions in Admin
On customer's edit page starting from AbanteCart 1.1.5 you can locate Transactions Tab. This page keep all transactions history for the customers account.
Transactions on storefront
Customers can spend the credit earned. In the checkout, just click the "Apply" button
All transactions can be seen by customer in the My Account > Transactions section.