curl --request POST \
  --url https://api.tilta.io/v1/merchants/{external_id}/mandates \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "iban": "DE03500105177178979259"
}
'

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({iban: 'DE03500105177178979259'})
};

fetch('https://api.tilta.io/v1/merchants/{external_id}/mandates', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

import requests

url = "https://api.tilta.io/v1/merchants/{external_id}/mandates"

payload = { "iban": "DE03500105177178979259" }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.tilta.io/v1/merchants/{external_id}/mandates",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'iban' => 'DE03500105177178979259'
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

{
  "mandate_id": "TLT PLT 00000001",
  "created_at": 1582896122,
  "updated_at": 1582896122
}

{
  "code": "BAD_REQUEST",
  "error": "Request validation failed. 1 issue found.",
  "issues": [
    {
      "code": "INVALID_TYPE",
      "path": "body.registered_at",
      "message": "Invalid type"
    }
  ]
}

{
  "error": "Unauthorized",
  "code": "UNAUTHORIZED"
}

{
  "error": "No Entity found",
  "code": "NOT_FOUND"
}

{
  "error": "Mandate with provided IBAN already exists for this Buyer",
  "code": "CONFLICT"
}