Problem during update api call in typeform

@picsoung or @mathio  @Harsh @jeremielp do any of you happen to have any advice on this? 

@mathio @Liz @Harsh  could you send me one dummy payload? how that json would looks like with my payload please? for now put the existing filed id as “field_id”.

After creating that form i received response as 

response1 :  {
  id: 'hfiBOz3P',
  type: 'form',
  title: 'demo typeform4',
  workspace: { href: 'https://api.typeform.com/workspaces/v3x4jA' },
  theme: { href: 'https://api.typeform.com/themes/qHWOQ7' },
  settings: {
    language: 'en',
    progress_bar: 'proportion',
    meta: { allow_indexing: false },
    hide_navigation: false,
    is_public: true,
    is_trial: false,
    show_progress_bar: true,
    show_typeform_branding: true,
    are_uploads_public: false,
    show_time_to_complete: true,
    show_number_of_submissions: false,
    show_cookie_consent: false,
    show_question_number: true,
    show_key_hint_on_choices: true,
    autosave_progress: true,
    free_form_navigation: false,
    use_lead_qualification: false,
    pro_subdomain_enabled: false,
    capabilities: { e2e_encryption: [Object] }
  },
  thankyou_screens: [
    {
      id: 'DefaultTyScreen',
      ref: 'default_tys',
      title: 'Thanks for completing this typeform\n' +
        "Now *create your own* — it's free, easy, & beautiful",
      type: 'thankyou_screen',
      properties: [Object],
      attachment: [Object]
    }
  ],
  fields: [
    {
      id: 'ENmFFAEmcLvI',
      title: 'Picture Choice Title',
      ref: '01H416151CQ6N5MH4F4VYQJP5F',
      properties: [Object],
      validations: [Object],
      type: 'picture_choice'
    },
    {
      id: 'vdtU2nsbiLMI',
      title: 'Picture Choice Title',
      ref: '01H416151CXMV1J4AFCYT809ZV',
      properties: [Object],
      validations: [Object],
      type: 'picture_choice'
    },
    {
      id: 'TjQUUbpsD779',
      title: 'Picture Choice Title',
      ref: '01H416151C2DG6VS5MZFWCYYYY',
      properties: [Object],
      validations: [Object],
      type: 'picture_choice'
    },
    {
      id: 'BLfXUF2vWeKW',
      title: 'Picture Choice Title',
      ref: '01H416151DYR1H2RKZN4RC98DY',
      properties: [Object],
      validations: [Object],
      type: 'picture_choice'
    }
  ],
  _links: { display: 'https://condenast-interactive.typeform.com/to/hfiBOz3P' }
}
and this is form link (https://condenast-interactive.typeform.com/to/hfiBOz3P)

now if I want to update this form basically add one more short_text field using api call then what this json will looks llike?

"fields":{"title": "First Name", "type": "short_text", "validations": { "required": true }}

Please provide me the correct format.

Already tried with this format 

var data = {

    "fields":[{"id": 'ENmFFAEmcLvI'},{"id": 'vdtU2nsbiLMI'}, {"id": 'TjQUUbpsD779'},{"id": 'BLfXUF2vWeKW'},{"title": "First Name", "type": "short_text", "validations": { "required": true }}]

}

but getting same error.

Pease help me in it.

The payload will be different for each typeform. First you need to retrieve the form, then modify that payload (eg. add new field) and send that full JSON to the update endpoint. Make sure you are using the PUT endpoint for updating the form.