curl --request GET \
  --url https://api.sandbox.asapp.com/conversation/v1/conversations/{conversationId}/messages \
  --header 'asapp-api-id: <api-key>' \
  --header 'asapp-api-secret: <api-key>'

{
  "items": [
    {
      "text": "Hello, I would like to upgrade my internet plan to GOLD.",
      "sender": {
        "role": "customer",
        "externalId": "123456"
      },
      "messageId": "01GMXE90AEV7H3J4DPBDKB1R79",
      "createdTimestamp": "2021-11-23T12:13:16.853Z",
      "clientTimestamp": "2021-11-23T12:13:14.555Z"
    }
  ]
}