Try to deploy app on Heroku

Hi All, Kindly help me out. I have stuck in this problem for last 3 days. I don’t have an idea where I am going wrong.
When I try to run my web app using “Heroku local” following happens.
a) connected to port 3002…
b) MongoDB connected successfully
But when I try to open on my browser with address “http://localhost:3002/”. I get error " This site can’t be reached"