Puma Web Server No Procfile detected, using the default web server (webrick)

Question

Attempting to use Puma Web Server with heroku for application. I have created a Procfile called "Procfile" with the following.

web: bundle exec puma -C config/puma.rb

I also have a config/puma.rb file with the following.

workers Integer(ENV['WEB_CONCURRENCY'] || 2)
threads_count = Integer(ENV['MAX_THREADS'] || 5)
threads threads_count, threads_count

preload_app!

rackup      DefaultRackup
port        ENV['PORT']     || 3000
environment ENV['RACK_ENV'] || 'development'

on_worker_boot do 
   ActiveRecord::Base.establish_connection
end

I receive the following warning in terminal

$git push heroku master

###### WARNING:
remote:        No Procfile detected, using the default web server (webrick)

Answer 1

$git run bash

Bash confirmed it was running

$ls 

All the files were shown. Procfile was being recognized with an extension as Procfile.rtf .

Deleted previous Procfile. Created another Procfile and made sure there was no extensions. Then ran the following:

$Git add .
$Git commit -m "Procfile" 
$Git push heroku master