> ## Documentation Index > Fetch the complete documentation index at: https://docs.ca.cryptoprocessing.com/llms.txt > Use this file to discover all available pages before exploring further. # Payment requests integration test cases These are the test cases to help you test your site's integration with CryptoProcessing [payment requests](https://docs.ca.cryptoprocessing.com/payment-requests/integration-guide.md). For each test case, create a new payment request via the [/payments/v1/requests](https://docs.ca.cryptoprocessing.com/api-reference/endpoints/payments.md) endpoint and then process the [payment\_request](https://docs.ca.cryptoprocessing.com/api-reference/callbacks/payment-request-callbacks.md) callback. For some test cases, you will need to check that your customer receives an email from CryptoProcessing and can click a link in it. Make sure to specify an email address you can access (`end_user_email`) when creating payment requests for such test cases. > [!NOTE] > > You can test payment requests in the sandbox environment by withdrawing funds from your merchant account instead of sending an external payment. Create a payment request, open the link, and choose a payment currency to get an address, then [withdraw funds](https://docs.ca.cryptoprocessing.com/withdrawals/create-a-withdrawal.md) to that address.
Procedure Expected results
**Successfully completed payment**
1. Create a payment request. 2. Open the payment request link on your device. 3. Place a payment for the exact amount requested. * The site gets a `payment_request` callback. * The callback status is `paid`. * The customer is redirected to `url_success`. * The customer receives an email about the successful payment.
**Overpayment**
1. Create a payment request. 2. Open the payment request link on your device. 3. Place a payment for an amount larger than requested (add more than the [minimum withdrawal amount](https://docs.ca.cryptoprocessing.com/confirmations-and-limits.md) plus the [refund fee](https://docs.ca.cryptoprocessing.com/payment-requests/fees.md), or the extra amount can't be refunded). * The site gets a `payment_request` callback. * The callback status is `paid`. * The customer is redirected to `url_success`. * The customer receives an email with a link to an automatic **partial refund**.
**Underpayment**
1. Create a payment request. 2. Open the payment request link on your device. 3. Place a payment for an amount less than requested (if you [accept underpayments](https://docs.ca.cryptoprocessing.com/payment-requests/underpayments.md#accept-underpayments), less than your tolerance allows). To get a refund, pay more than the [minimum withdrawal amount](https://docs.ca.cryptoprocessing.com/confirmations-and-limits.md) plus the [refund fee](https://docs.ca.cryptoprocessing.com/payment-requests/fees.md). 4. Wait until the payment request's lifespan or [rate lock](https://docs.ca.cryptoprocessing.com/payment-requests.md#lifespan-and-rate-lock) ends, whichever comes first. * When the payment request ends, the site gets a `payment_request` callback. * The callback status is `failed`. * The customer is redirected to `url_failed`. * The customer receives an email with a link to an automatic **full refund**.
**Accepted underpayment** (if you [accept underpayments](https://docs.ca.cryptoprocessing.com/payment-requests/underpayments.md#accept-underpayments))
1. Create a payment request. 2. Open the payment request link on your device. 3. Place a payment for an amount less than requested, but within your underpayment tolerance. 4. Wait until the payment request's lifespan or [rate lock](https://docs.ca.cryptoprocessing.com/payment-requests.md#lifespan-and-rate-lock) ends, whichever comes first. * When the payment request ends, the site gets a `payment_request` callback. * The callback status is `paid`, and its `status_reason` says the underpayment was accepted. * The callback's `currency_received` is the amount actually received, converted to the payment request currency.
**Payment requests with a late payment**
1. Create a payment request with a short lifespan (for example, 5 minutes). 2. Open the payment request link on your device. 3. Choose a payment currency and click **Proceed to payment**. 4. Copy the address or scan the QR code with your device. Do not place the payment yet. 5. Wait till the payment request expires. 6. Place a payment for the requested amount. * The site gets a `payment_request` callback with the `expired` status when the payment request expires. * After the late payment is confirmed, the site gets another `payment_request` callback. Its status is still `expired`, and the transaction has `late_payment` set to `true`. * The customer is redirected to `url_failed`. * The customer receives an email with a link to an automatic **full refund**.
**Payment request expired before the currency selection**
1. Create a payment request with a short lifespan (for example, 5 minutes). 2. Wait till the payment request expires. * The site gets a `payment_request` callback. * The callback status is `expired`. * The customer is redirected to `url_failed`. * The customer does not receive any email.
**Payment request expired after the currency selection**
1. Create a payment request with a short lifespan (for example, 5 minutes). 2. Open the payment request link on your device. 3. Choose a payment currency and click **Proceed to payment**. Do not place the payment. 4. Wait till the payment request expires. * The site gets a `payment_request` callback. * The callback status is `expired`. * The callback contains the information about the selected currency in the `currency_sent` field. * The customer is redirected to `url_failed`. * The customer does not receive any email.
This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.