curl --request PUT \
  --url https://api.interchange.io/api/v2/messaging-apps/{definitionId}/installations/{installationId}/identity \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "externalActorId": "<string>",
  "userId": 4503599627370495
}
'

import requests

url = "https://api.interchange.io/api/v2/messaging-apps/{definitionId}/installations/{installationId}/identity"

payload = {
    "externalActorId": "<string>",
    "userId": 4503599627370495
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.put(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'PUT',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({externalActorId: '<string>', userId: 4503599627370495})
};

fetch('https://api.interchange.io/api/v2/messaging-apps/{definitionId}/installations/{installationId}/identity', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

{
  "linked": true,
  "userId": 4503599627370495
}

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}

{
  "data": null,
  "error": {
    "code": "<string>",
    "message": "<string>",
    "field": "<string>",
    "details": {}
  }
}