Heroku Application Error - How can I open my app?

I'm trying to open my simple web app (Spring Boot) on Heroku but it shows me an "Application Error". I created a Procfile and that stuff but that didn't help. The web app works perfectly local. I used the command "heroku logs" and it shows me the error "No web process running". As I said if I run it locally it works. Would appreciate any help.enter image description here