For you to set up multiple group lunches, you may follow the steps below:
- Navigate to Calendar.
- Go to the date that you'd like to set a group lunch.
- Click on Start a Group Lunch

From there, you'll be able to set multiple group lunch in a day.
For more references, please watch the video below:
https://www.useloom.com/share/e2728c3630c9488b9e54140617c3104b