curl --request DELETE \
  --url https://api.lemlist.com/api/campaigns/{campaignId}/leads/{leadIdOrEmail}/steps/{stepId}/personalization \
  --header 'Authorization: Basic <encoded-value>'

import requests

url = "https://api.lemlist.com/api/campaigns/{campaignId}/leads/{leadIdOrEmail}/steps/{stepId}/personalization"

headers = {"Authorization": "Basic <encoded-value>"}

response = requests.delete(url, headers=headers)

print(response.text)

const options = {method: 'DELETE', headers: {Authorization: 'Basic <encoded-value>'}};

fetch('https://api.lemlist.com/api/campaigns/{campaignId}/leads/{leadIdOrEmail}/steps/{stepId}/personalization', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

require 'uri'
require 'net/http'

url = URI("https://api.lemlist.com/api/campaigns/{campaignId}/leads/{leadIdOrEmail}/steps/{stepId}/personalization")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Delete.new(url)
request["Authorization"] = 'Basic <encoded-value>'

response = http.request(request)
puts response.read_body

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.lemlist.com/api/campaigns/{campaignId}/leads/{leadIdOrEmail}/steps/{stepId}/personalization",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "DELETE",
  CURLOPT_HTTPHEADER => [
    "Authorization: Basic <encoded-value>"
  ],
]);

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

curl_close($curl);

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

{
  "reset": true
}

{
  "error": "Validation error",
  "code": "VALIDATION_ERROR"
}

"The authentication you supplied is incorrect"

{
  "error": "Lead not found in this campaign",
  "code": "REVIEW_DRAFT_LEAD_NOT_FOUND"
}

{
  "error": "The lead already reached this step: its message can no longer be personalized",
  "code": "REVIEW_DRAFT_STEP_ALREADY_REACHED"
}

{
  "error": "This step type cannot be personalized for a lead",
  "code": "REVIEW_DRAFT_STEP_UNSUPPORTED"
}