Custom fields not being saved

Question

I'm using propertybase to create contacts via salesforce (it uses apexrest REST API) and I followed this guide: https://help.propertybase.com/hc/en-us/articles/360003180752-WebToProspect-REST-API

I'm sucessfully creating contacts but I'm having problem with custom fields. When I try to save custom fields (that ends with __c, eg: Gender__c) I got no errorMessage but the contact is created with only the default fields populated (FirstName, Email, etc..). None of the custom ones are saved (there are text and pick list types, but none of them works).

The json for the request is something like that

{
  "prospect": {
    "token" : "tokenCode",
    "contact": {
      "FirstName": "A1Test",
      ... other default fields
      "Gender__c": "Male",
      ...other custom fields
    },
    "contactFields": [
      "FirstName",
      ...
      "Gender__c",
      .....
    ]
  } 
}

Should I change something in the request? Can someone help with that?

Answer 1

Thanks @Derek, I had enabled the read/write permission of the fields when I created them but when I went to Object Settings the checkbox weren't marked for the fields. So it was just checkin them there and I could save the data.

Answer 2

It seems need to use fieldName and label end with "__c".