Couldn't find that process type, Heroku
This may happen if your procfile is misspelt, such as "procfile" or "ProcFile" etc. The file name should be "Procfile" (with a capital P).
sometimes changing the file name is not anough, because git wouldn't spot the change. I had to delete the Procfile completely, then commit the change, than add it again with the right name, and then commit that again:

remove your procfile
git commit
add a new procfile with the exact name "Procfile"
commit again
git push heroku master (or main - new heroku projects now uses main)

should work!
I'm trying to deploy a simple python bot on Heroku but I get the error
couldn't find that process type 
When I try to scale the dynos. I already made a procfile and it looks like this:
web: gunicorn dep:app, where "dep" is the name of my python code  
What could be the reason?