shorten url returning 504

Hi, while calling botan.shorten_url in python I get the following response:
<html>
<head><title>504 Gateway Time-out</title></head>
<body bgcolor="white">
<center><h1>504 Gateway Time-out</h1></center>
<hr><center>nginx/1.9.9</center>
</body>
</html>
did I make the request wrongly or something is down?