When I try to make any simple request from my system to the Sell API I get 500 error

Here's my code on python:

import http.client

conn = http.client.HTTPSConnection("api.getbase.com")

payload = ""

headers = {
    'Content-Type': "application/json",
    'Accept': "application/json",
    'Authorization': "Bearer *************"
    }

conn.request("GET", "/v2/deal/custom_fields", payload, headers)

res = conn.getresponse()

data = res.read()

print(data.decode("utf-8"))

Here's my code on PHP

$ch = curl_init();

$url = "https://api.getbase.com/v2/deal/custom_fields";
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Content-Type: application/json',
    'Accept: application/json',
    'Authorization: Bearer **********'
]);
$response = curl_exec($ch);
        
curl_close($ch);

Here's my code on JS:

const options = {
method: 'GET',
headers: {
    'Content-Type': 'application/json',
    Accept: 'application/json',
    Authorization: 'Bearer ***************'
    }
};

fetch('https://api.getbase.com/v2/deal/custom_fields', options)
.then(response => response.json())
.then(response => console.log(response))
.catch(err => console.error(err));

All of the above returns this

500 Internal Server Error
nginx

that's not an error from my server.

however, the code works good in postman. What I am missing?