While designing the Nintex form , I came across one issue "Unexpected error" and validation rules I have set where not getting fired .
Using developer tool (F12) , I found that i am getting "Unexpected error" in form when saving the form.
I re-checked all my rules and found now fault.
Later i debug the code using "developer tool" and added breakpoints at and found that id of the element where it is failing.
When i check the field in Nintex form found that actual issue was when we add any condition in Nintex Form in Custom Validation function
And then later we select “No”
But still the above function will be available in form during runtime and create problem.
Solution: Remove All the “Custom Validation Function” before setting the “Use custom Validation” as “NO”