Required option not working on the first question of this form

I think it's a bug and the preset slider positions are telling JF that required fields are filled in. I thought I tested it and it worked, but not working for me now.  You can click next without prompt to adjust sliders.  https://eatballard.com/deposit-gift-cards/ 

Unless you choose Checkbox, Radio Button, and Dropdown, the field is considered filled considering that it is preselecting Important from the list. It is required but prefilled so that's why users can freely move to the next page of the form. I see no problem here. That's how it works. 

ok