GHL Custom Fields API problem

How To
1

Hi everyone, I’m trying to build an automation that creates an opportunity in a sales pipeline in Go High Level. However, when I try to use a custom field in the HTTP module, I keep getting errors.

I’ve attached my current HTTP configuration below.

Can someone please help me figure out what I’m doing wrong? What is the correct endpoint for creating an opportunity? How should I structure the request? Any guidance would be really appreciated.

Method Post:-

https://rest.gohighlevel.com/v1/opportunities

Authorization
Bearer (my API)

Content-Type
application/json

{
  "name": "Opportunity Name",
  "pipelineId": "Ph9rYPAgWfjf5x5He5jw",
  "stageId": "dfd1478a-bjgu-48c1-9d13-be22c4c8ccfc",
  "status": "open",
  "contactId": "pRH4MFHIjebIJG3xIK5k",
  "value": 1000,
  "customFields": {
    "opportunity.solicitation_number": "123456"
  }
}

Thank you in advance!