I am working with Oracle Integration Cloud (OIC) and have encountered a challenge. I need to combine the responses from two different APIs into a single payload.

I am trying to do a POC where I want to connect to the Oracle Db hosted on AWS using OIC Connection and create a Sales Order.
The POC is to remove ORDS as a integration middleware and use OIC instead.
For this, I have signed up with a free tier Oracle Cloud Account and launched an Integration Instance. Under the service console I have tried to create a connection by giving details to the DB server.
Whenever I test this connection, I get a error like below:
The connection test failed. Check your connection and use agent from agent group.

I want to pass dynamic request payload JSON. I am using stored procedure with Varchar2 IN and Varchar2 OUT parameters.