Nginx/PHP-FPM/Laravel cannot handle concurrent requests with single IP

We have two servers:

• Nginx/PHP-FPM/Laravel
• Python on a different server

Some API calls to Laravel need data from the python server and vice versa. But when both of these occur it appears to be blocking.

1. My IP makes a call to the Laravel server.
2. Laravel server makes a call (guzzletransport) to python and waits for a response.
3. Python server makes a request back to the Laravel server in part of completing the request. This call never completes under these conditions.

I can test the call in (3) by making the appropriate call to the python server and it completes without issue. It appears that the call in (2) blocks the server from processing any additional requests. I am confused why this is occurring as php-fpm should allow simultaneous connections.

While waiting for (1) from my browser and additional requests from my browser also are blocked. I can make requests during this time to the Laravel server from a different IP and it completes it without issue.