I have a handful of validation rules that were working perfectly fine and now have stopped. I can't tell what happened.
Can you "debug" the form and see if there is any scripting error?
Have you custom scripting?
It use to be an error on script that makes fail validations
I'm not very technical at all...I would need help understanding how to debug. I don't have any custom CSS or Java that I am aware of.
in browser press F12 and switch to Console tab in window that pops up.
then go and run your form. check console log for any errors reported.