Issue with multiple users accessing my Flet Web App

Question

I'm developing a web application using Flet and Python, and I'm hosting it on Railway. My goal is to have a single instance of my app running, allowing multiple users to connect without issues, just like a normal web app.

However, I'm encountering a problem:
**-** When I run my app locally using (basically running the app and binding the port 8000):
```flet run .\main.py -w -p 8000```
It works fine

**-** But if I try to start another instance on the same port, I get this error:
```ERROR: [Errno 10048] error while attempting to bind on address ('::', 8000, 0, 0): [WinError 10048] only one usage of each socket address (protocol/network address/port) is normally permitted```

**-** Also, when deployed on Railway, it seems like every new user request tries to bind the port again, which shouldn't happen.

**What I'm trying to achieve:**
**-** I want my app ro run as a single instance where multiple users can cnnect, just like any website
**-** Each user should have their own session without interfering with others

**My current code (simplified)**
```import flet as ft
import os

def main(page: ft.Page):
    page.title = "My Flet App"
    page.add(ft.Text("Hello, world!"))

PORT = int(os.environ.get("PORT", 8000))  # Use Railway's assigned port

ft.app(target=main, port=PORT, view=ft.WEB_BROWSER)  # Start server```

**Useful Link**
I've been searching for a while and found this in Railway's documentation:
"**Note:** If your application needs to be accessible over both public and private networks, your application server must support dual stack binding. Most servers handle this automatically when listening on ::, but some, like Uvicorn, do not."

link to this doc: https://docs.railway.com/guides/public-networking

Can someone help me?