I did a bit more digging into the Postman code that was able to run successfully and got the correct answer from that. Here’s the code I used to correctly run the API and pass the information cross-domain.
// Set URL to the Create patient endpoint const Url = "https://cors-anywhere.herokuapp.com/https://staging.micromerchantsystems.com/mmsgatewayapistaging/api/patient/create"; // On button ajax call to create a new user with the above data $('.btn').click(function () { // The input value variables NEED to be defined and set after the click function // so that the value can be received and passed into the userData variable. // Define User data here ** Currently static information ** // Need to set variables based on input value to the correct identifier // EX: "FirstName": $('#first_name').val(); var user_firstName = $("#first_name").val(); const userData = { "RequestingClient": { "ClientId": "XXXXXX", "MemberId": "XXXXXXX" }, "Pharmacy": { "IdentifierType": 2, "Identifier": "XXXXXXX" }, "LastName": "Test", "MiddleInitials": "X", "FirstName": user_firstName, "Gender": "M", "DOB": "01/01/1990", "Email": "[email protected]", "PhoneNumber": "1234567890", "MobileNumber": "1234567890", "BusinessNumber": "1234567890", "PatientIdentifiers": [ { "IdentifierType": 1, "IdentifierType": "12345" }