Unable to get attendees list

{ "int_error_code":"404 NOT FOUND", "msg":"Resource Not Found" }

Getting as above when I am trying to get attendees list through php coding.

$curl = curl_init();

curl_setopt_array($curl, array(
CURLOPT_URL => "https://api.getgo.com/G2M/rest/meetings/507667685/attendees",
CURLOPT_RETURNTRANSFER => true,
CURLOPT_ENCODING => "",
CURLOPT_MAXREDIRS => 10,
CURLOPT_TIMEOUT => 0,
CURLOPT_FOLLOWLOCATION => true,
CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
CURLOPT_CUSTOMREQUEST => "GET",
CURLOPT_HTTPHEADER => array(
"Content-Type: application/json",
"Accept: application/json",
"Authorization: Bearer eyJraWQiOiJvYXV......"
),
));

$response = curl_exec($curl);

curl_close($curl);
echo $response;