I can't authenticate my application

require_once 'config.php';
try {
    $client = new GuzzleHttp\Client(['base_uri' => 'https://zoom.us']);
    $response = $client->request('POST', '/oauth/token', [
        "headers" => [
            "Authorization" => " Basic ZjZXdDB0SFpTUlN3MGxPV0twRFlROlZBNnpqTTJoSjFjQUs0MDZUTnB5blA2NUU1dTExZXJJ"
        'form_params' => [
            "grant_type" => "authorization_code",
            "code" => $_GET['code'],
            "redirect_uri" => REDIRECT_URI
    $token = json_decode($response->getBody()->getContents(), true);
    $db = new DB();
    echo "Access token inserted successfully.";
} catch(Exception $e) {
    echo $e->getMessage();
this is my callback, it looks all right but it makes me this error:

Client error: POST https://zoom.us/oauth/token resulted in a 400 Bad Request response: {“reason”:“Bad Request”,“error”:“invalid_request”}

Hey @a.s.rwar
Thanks for reaching out to the Zoom Developer Forum.
Were you able to troubleshoot this issue?

Did you ever get past this issue? If so how?

Hi @geoff.crego
It looks like we did not get a response here.
Are you experiencing this on your end?