Does that API support multiple records at the same time?
If not, then you might need to create some sort of loop, or a data driven test using the test runner.
Is there any error information returned by the API?
If you are new to Postman. I would recommend going through the Postman training if you havenāt done so yet.
Postman Galaxy Training | Postman API Network
Run through the āAPIs 101 Trainingā, then the āTesting and Automation Trainingā course.
The following links provide a bit more info about data driven testing.
Importing data files | Postman Learning Center
API Testing āA Beginners Viewā: Data-driven testing in Postman - Community showcase - Postman