Make clients writen in Unity listen to when my azure function endpoint

I am writing a simple app. I will have one client make an HTTP request and I want every other client to know that the request was made.
Here is my example:

endpoint: URI exampleURI = new URI("exampleuri.azurewebsites.net/api/shootshot");

Client one on a mobile device anywhere in the world
hits exampleURI via UnityWebRequest and passes
bulletData
{
bulletID: 000000,
bulletPosition:x,y,z
}

All other Clients on whatever device anywhere else in the world
see that the request was made and can see bulletData that was passed to the endpoint.

This works on localhost of course because I can just use the HttpListener class (c#). But when I try to listen to my function app that's hosted in azure, it won't actually track it.

I know this is definitely due to my lack of knowledge of how HTTP listening is done. Now I'm trying to learn