how to change the heroku app you are editing in heroku cli code example
Example 1: heroku restart
heroku ps:restart web -a <my app name>
Example 2: heroku restart rails server
heroku restart -a app_name
# The -a is the same as --app
heroku ps:restart web -a <my app name>
heroku restart -a app_name
# The -a is the same as --app