How to Configure Request Body JSON of an Action with Dynamic/Custom Fields

{
"email": "[email protected]",
"name": "John",
"fields": {
  "company": "MailerLite",
  "address": "B 20, White Street, Banglore",
  "phone": "+14568455487",
  "zip": 4566685
}
}

{
    "email": "{{email}}",
    "name": "{{name}}",
    "fields": {
        "pabbly_custom_fields": {
            "{{pabbly_custom_key}}": "{{pabbly_custom_value}}"
        }
    }
}

{
   "contact": {
  "email": "[email protected]",
  "firstName": "John",
  "lastName": "Doe",
  "phone": "7223224241",
  "fieldValues": [
   {
    "field": "1",
    "value": "The Value for First Field"
   },
   {
    "field": "6",
    "value": "2008-01-20"
   }
  ]
}
}

{
       "contact": {
        "email": "{{email}}",
        "firstName": "{{firstName}}",
        "lastName": "{{lastName}}",
        "phone": "{{phone}}",
        "fieldValues": {
            "pabbly_custom_fields": [
                {
                    "field": "{{pabbly_custom_key}}",
                    "value": "{{pabbly_custom_value}}"
                }
            ]
        }
    }
}

{
"email": "[email protected]",
  "name": "John Doe",
  "fields": {
    "email": "[email protected]",
    "name": "John",
    "last_name": "Doe",
    "zip": "99901",
    "mobile_number": "8889888988",
    "business_address": "912 Park Ave, Ketchikan, Alaska, USA"
  }
}