curl --request POST \
  --url https://cloud.datafyapi.com.br/ig/me/messages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "recipient": {
    "id": "1000000000000001"
  },
  "sender_action": "mark_seen"
}
'

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({recipient: {id: '1000000000000001'}, sender_action: 'mark_seen'})
};

fetch('https://cloud.datafyapi.com.br/ig/me/messages', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://cloud.datafyapi.com.br/ig/me/messages"

payload = {
    "recipient": { "id": "1000000000000001" },
    "sender_action": "mark_seen"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

{
  "recipient_id": "1000000000000001"
}

{
  "error": {
    "message": "Não foi possível encontrar o usuário solicitado.",
    "type": "IGApiException",
    "code": 100,
    "error_subcode": 2534014,
    "fbtrace_id": "AbCdEfGhIjK"
  }
}

{
  "statusCode": 401,
  "message": "Token inválido ou não encontrado."
}

{
  "statusCode": 402,
  "message": "Assinatura inativa (status: canceled). Ative sua assinatura no painel para voltar a usar a API."
}