If the meal service icon/hyperlink is present at time of booking and you don't receive a meal, complain. If DL ignores its published 'meals at meal time' guidelines and you don't get a meal, complain.
https://www.delta.com/content/www/en...rst-class.html
If there's a
force majeur event - oh, like the DTW flight kitchen burning to the ground six hours before my DTW-departing flight - I'll cut them some slack.