I'm working to upgrade from 2019R1 to 2021R2.

Credit card processing is quite different in 21R2 than I'm familiar with. I need some direction for how to process Sales Orders with Credit Cards using the REST API in 21R2.

I'm currently using the REST API to insert Sales Orders with a credit card payment (authorized only, not captured) using the SalesOrder endpoint. As part of the API call to the SalesOrder endpoint, I only have to provide the PaymentMethod and external PreAuthorizationNbr. This corresponds to a tab in the SO called "Payment Settings". It works great, but no longer exists in 21R2. 

I understand that I now need to use the Sales Order -> Payments tab, but it's not clear to me how to associate the external pre-authorization with the Payment and Application using the REST API.

Can anyone point me to documentation or examples or using the REST API to insert Sales Orders with pre-authorized (or even captured) credit card transactions.

Should I use the REST API to build a Payment and Application first? Then process the Sales Order second? How do I get Acumatica to validate or import the externally processed pre-authorization using the REST API? I’m struggling to get anything to work when using the Sales Order endpoint only.

What is the best practice for processing and associating externally processed credit cards and payments using the REST API in 21R2?

- Ben