403 Forbidden error when using the service

**Describe the bug**
I'm getting a 403 Forbidden error when trying to use codex-lb.

Error message：
```
unexpected status 403 Forbidden: <html>
<head><title>403 Forbidden</title></head>
<body>
<center><h1>403 Forbidden</h1></center>
<hr><center>nginx</center>
</body>
</html>
```