curl --request GET \
  --url https://api.lemlist.com/api/team/dynamic-sender-exclusions \
  --header 'Authorization: Basic <encoded-value>'

import requests

url = "https://api.lemlist.com/api/team/dynamic-sender-exclusions"

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

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

print(response.text)

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

fetch('https://api.lemlist.com/api/team/dynamic-sender-exclusions', 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/team/dynamic-sender-exclusions")

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

request = Net::HTTP::Get.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/team/dynamic-sender-exclusions",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  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;
}

{
  "data": {
    "senders": [
      {
        "userId": "usr_T2wWj3GOt0hXms721",
        "channels": [
          {
            "type": "email",
            "id": "usm_oZOkr8H1oFjgvDI6J"
          },
          {
            "type": "linkedin"
          }
        ]
      },
      {
        "userId": "usr_ll2LqAVvLk75ER9fv"
      }
    ]
  }
}

The authentication you supplied is incorrect

route is available starting emailPro plan

{
  "error": "Route bad method",
  "code": "ROUTE_BAD_METHOD"
}