If the hours are empty and the field is required, it is still validated

I add an "Office hours" field, I check the "Required field" box. When I create a form, and the "Office hours" field is empty, the form can still be validated.
Normally it should display an error message to say that the chapter "Office hours" is required.

Thanks, it works ;-)

But the template to display the schedules in the form is disastrous. We really have to deal with the problem of responsive design. The schedules are unusable on the desktop when there are error messages and it is even worse on mobile.