# Support
source: https://developer.mastercard.com/payment-acceptance-api/documentation/support/index.md

## FAQ {#faq}

### General {#general}

The Payment Acceptance API provides a unified approach for accepting B2B card-based payments across multiple regions, acquiring partners, and gateway channels. It simplifies card acceptance while maintaining security, reliability, and operational efficiency. The API receives payment instructions routed by Commercial Direct Payments (CDP) based on the Creditor's preferences. CDP also sends payment status updates to both Debtors and Creditors throughout the transaction lifecycle. The Payment Acceptance API is primarily used by Creditor Agents, acting on behalf of Creditors, to receive, authorize, and manage card payment instructions routed by CDP. The Creditor Agent receives the payment instruction and processes it on behalf of the Creditor. This includes authorizing, accepting, or rejecting the payment as required. The Mastercard Payment Acceptance API uses OAuth 1.0a for authentication and Mastercard encryption.

### Onboarding {#onboarding}

Access to the Mastercard Payment Acceptance API requires completing onboarding and environment setup with Mastercard. Complete the Sandbox onboarding steps to validate authentication and integration. Finalize the required onboarding prerequisites to enable Production access. For detailed onboarding steps, follow our onboarding guide in the [Quick Start Guide](https://developer.mastercard.com/payment-acceptance-api/documentation/quick-start-guide/index.md). Mastercard's Customer Implementation Service (CIS) team will help you through the onboarding process for each environment (Sandbox, Production). Once the connectivity is established successfully, you can start using the APIs. There are two environments where onboarding is performed: Sandbox test environment is used for API stubs with simulated, static responses. It is intended to be used by developers who want to explore using the Mastercard Payment Acceptance API without formally entering into an agreement with Mastercard. It contains sample data and an ability for developers to test their code, so they can determine if the functionality offered meets their needs. Production environment is used for commercial deployments. You have three options when it comes to renewing your keys. This [article](https://developer.mastercard.com/platform/documentation/getting-started-with-mastercard-apis/renewing-your-keys/) provides in-depth information on the approaches that you can take. Mastercard Payment Acceptance API keys expire after one year due to service restrictions.

### Integration {#integration}

A Creditor Agent retrieves payment instructions by submitting an authenticated GET request to the Payment Acceptance API using the ICA and `instruction_identification` values issued by CDP, after the payment instruction has been routed. For usage details and examples, refer to the [Card Payment Status Inquiry](https://developer.mastercard.com/payment-acceptance-api/documentation/use-cases/card-payment-status-inquiry/index.md). When a Creditor is not registered, the card payment request and remittance data are delivered through the Mastercard email service. A secure email containing the payment details is sent to the Creditor. Testing should begin in the Sandbox environment using the Reference Application or Insomnia with the Mastercard plugin. The cancellation is accepted or rejected depending on timing.

* Execution date today or future: CDP coordinates cancellation with the Creditor Agent.
* Execution date in the past: The cancellation request is rejected.
CDP sends incremental payment status updates (for example, SUBMITTED, APPROVED, DECLINED, SETTLED) to both Debtor and Creditor Agents. Review the [Codes and Formats](https://developer.mastercard.com/payment-acceptance-api/documentation/code-and-formats/index.md) section to identify error causes related to authentication, identifiers, or invalid state transitions.

### Policy {#policy}

While there is no throttling policy, Mastercard reserves the right to limit user requests to preserve the reliability of the system. Yes, the Payment Acceptance API is payment card industry compliant.

### Performance {#performance}

The average response time is 0.5 seconds, with peak latency rarely reaching up to 3 seconds. The Throughput per Second (TPS) per customer is 12 requests per second.

### Support {#support}

In the event that your team experiences issues, write to [API Support Team](mailto:apisupport@mastercard.com), and outline the following:   

* Email Subject: Payment Acceptance API: Issue with (Describe Issue Here).
* Body: Include details about the nature of the request, along with screenshots if possible to help expedite the resolution.
[The API Status Page](https://developer.mastercard.com/api-status) informs Mastercard Developers users of the status of each API.

## Get Help {#get-help}

### Contact us for Technical Support. {#contact-us-for-technical-support}