post https://api-sandbox.retail.monext.com/v1/checkout/sessions
[DEPRECATED] Please see "Payment / Session" section
Creating a payment session generates a session token:
A temporary key used to initialize the Payment Widget and authenticate it against your account.
This works the same way with Hosted Payment Pages.
Payment Widget automatically retrieves all the settings from the payment session to configure the payment methods and the payment experience.
Note: sessionId expire after 30 minutes per default.