Is it possible to create a customer record with contact in REST API?

Hello, trying to create Customer record via postman, Customer record with address is created with no problems, but having difficulties around adding contact:

when using code below, Customer record is created but not contact:

error code: X-NetSuite-PropertyValidation: Unknown field name contactroles. The field does not exist on this record instance.

       "contactroles": {

                    "items": [{

               "Contact": {

                    "title": "CTO",

               "subsidiary": { "id": "5" },

                  "entityId": "first last",

                     "email": "api@api.com.au",

                     "phone": "0400000000"

                    }}]

                    

            }

i tried using "contactlist", but also receive an error.

As far as i see Customer record API is no longer in Beta so maybe there is a solution ?

Thanks