> For the complete documentation index, see [llms.txt](https://docs.galaxypay.vn/upc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.galaxypay.vn/upc/payment-gateway/api-specification/management.md).

# MANAGEMENT

## [**Query Transaction**](/upc/payment-gateway/api-specification/management/query-transaction.md) 

**Query Transaction** is the process of retrieving information about the status and details of a transaction that has been completed. This operation allows the system or merchant to check information such as:

* **Transaction Status**: Verifying whether the transaction has been completed, canceled, is pending, or declined.
* **Transaction Details**: Retrieving information like the amount, transaction ID, transaction time, and payment method.
* **Additional Information**: This may include error reasons (if the transaction failed), update history, or merchant-specific custom data.

## [Refund Transaction](/upc/payment-gateway/api-specification/management/refund-transaction.md)

**Refund Transaction** is the process of returning funds to the buyer after a transaction has been completed and the payment has been captured. This typically occurs when the buyer returns goods, cancels services, or if there was an issue with the transaction.

* **Initiated by the Merchant**: The merchant initiates the refund, either fully or partially, depending on the circumstances (e.g., product return, service dissatisfaction).
* **Post-Capture**: Refunds can only be issued after the transaction has been successfully captured and funds have been transferred to the merchant.
* **Reverses the Payment**: The refund process essentially reverses the captured payment, returning the funds from the merchant’s account back to the buyer’s account.

## [**Void Transaction**](/upc/payment-gateway/api-specification/management/void-transaction.md)

**Void Transaction** is the process of canceling a transaction that has been **authorized** but not yet **captured**. When a transaction is **voided**, the entire transaction is canceled, and no funds are transferred from the buyer’s account to the merchant’s account.

* **Cancel Before Capture**: A **void** is only applicable to transactions that have been authorized but not captured. When voided, the payment does not go through.
* **No Funds Debited from the Buyer’s Account**: Since the transaction has not been captured, no money is deducted from the buyer's account.
* **Quick Processing**: A void transaction is typically processed quickly and does not require a long period to reverse, as no funds have been transferred.

## [**Capture Transaction**](/upc/payment-gateway/api-specification/management/capture-transaction.md)

**Capture Transaction** is the process in payment systems where the funds that were previously authorized for a transaction are officially transferred from the buyer’s account to the merchant’s account. This step finalizes the payment, ensuring that the merchant receives the funds.

* **Authorization** (the initial step) places a hold on the funds in the buyer's account, but does not transfer them.
* **Capture** is the action that moves the funds from the buyer’s account to the merchant's account, completing the transaction.