Payment service providers offer the possibility to test their function using a test or sandbox account. In the plenigo Merchant Backend this test data can be stored in the stage account to test payments and transactions prior to going live.
Stripe provides test payment methods to be used in a test checkout.
Paypal and Amazon Pay provide sandbox accounts (test customers) which can be created and used in the checkout.
The following Knowledge Base entries lead you through the setup of a test account:
PayPal: Create a PayPal Sandbox account
Amazon Pay: Amazon Pay Test Accounts
Stripe Test Zahlungsmittel: https://docs.stripe.com/testing