Heroku getting at=error code=H10 while deploying python Flask web app

I am trying to deploy my first flask application in heroku. Followed steps exactly as mentioned in heroku documentation. But It is throwing Application error as shown below

2021-07-18T12:55:34.315320+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/favicon.ico" host=eflask-simple-app.herokuapp.com request_id=30d3a699-6f05-4783-a5f5-40c9717af881 fwd="117.213.244.13" dyno= connect= service= status=503 bytes= protocol=https

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Project Structure

app
    main.py
Pipfile
Pipfile.lock
Procfile
requirements.txt
runtime.txt
wsgi.py

wsgi.py file

from app.main import app
import os 

port = int(os.environ.get("PORT", 5000))
if __name__ == "__main__":
        app.run(host='0.0.0.0', port=port, debug=True)

Procfile

web: gunicorn --bind 127.0.0.1:5000 wsgi:app

app/main.py

from flask import Flask

app = Flask(__name__)

@app.route("/")
def home_view():
        return "<h1>Welcome to Flask</h1>"

requirements.txt

click==8.0.1
colorama==0.4.4
Flask==2.0.1
gunicorn==20.1.0
itsdangerous==2.0.1
Jinja2==3.0.1
MarkupSafe==2.0.1
Werkzeug==2.0.1

runtime.txt

python-3.9.6

Answer

Welcome to Stackoverflow @vishnuvreddy

Since you are deciding port using

port = int(os.environ.get("PORT", 5000))

and mentioned --bind in Procfile as below

web: gunicorn --bind 127.0.0.1:5000 wsgi:app

conflict each other.

Solution

Change Procfile to

web: gunicorn wsgi:app