One of the questions on the form is preventing to submit the form

One of the questions on the form (please specify the number o tables required) is preventing submission if left empty the even though in the settings 

I have checked your JotForm and when I try to submit the form, I see that the error message is being displayed for the field 'If attending Friday evening, please specify the number of tickets required'

This is due to the limit set for the field as the minimum and maximum entry.

I was able to submit the form, by changing the number to 1. Let us know if you still experience any issue or referring to something different. We will be happy to help.

Thanks!