SAP ByD Supplier Invoice Payment via API Integration

Well, currently we are integrating an internal system with our SAP ByD. What we need to do is to integrate SAP ByD with our payment systems. So, we pay all our suppliers via ACH right now and we would like to update it on SAP automatically. Right now, using OData custom services, we were able to get the suppliers, invoices and house bank accounts into our system. However, what we need to achieve is an automated update between our system and SAP telling it we paid some invoices with a specific bank account via ACH. I was under the idea that would exist an API that I could send this information and SAP would update it. Does anyone knows if this can be achieved? I looked into a lot of API's these days and couldn't find a way to do it.