1、Login to the shop with the main account and enter the back office -> Select Receipt -> Add Receipt Method
2、Search by payment provider: Oceanpayment->Enable
3、Find Oceanpayment-Klarna->Fill in Account, Securecode, Terminal in order according to the content of the email ->Check the box to automatically synchronize the waybill number ->Activate
4、Select a product to place an order to test, can jump to the payment page