# Submit payment instruction

`POST /devices/{serialNumber}/payment-instructions`

Use this method to submit an instruction request to initiate a sale on a payment device.  

In the request, include the order amount and currency.  

When you send a successful request, our gateway returns information about the payment instruction and a paymentInstructionId, which you need for the following methods:
- [Retrieve payment instruction](https://docs.payroc.com/api/schema/payroc-cloud/payment-instructions/retrieve) - View the details of the payment instruction.
- [Cancel payment instruction](https://docs.payroc.com/api/schema/payroc-cloud/payment-instructions/delete) - Cancel the payment instruction.