After trying to fix the below error for many days, I decided to post the error, hoping that someone can help me to figure it out. Note: I added a link to my git repository as well.
Here is the error of my log:
2020-05-04T17:42:26.314508+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=cactus-restaurant.herokuapp.com request_id=202dfecf-cfb0-4349-bd51-101b4f481ace fwd="91.139.187.213" dyno= connect= service= status=503 bytes= protocol=https