Why isn't shipping being added when some of my products are selected?

I have a party form that has 36 items. I just had a customer purchase 1 item and it didn't charge her shipping. My shipping charge is set at $3 flat rate per order. I went onto the form after that and tested it. It's not charging shipping on any of the new items that I have added.  It's only charging it on the original items from when I first created the form. Please help me fix this. I can't afford not to have the shipping paid.

It was most probably a glitch, I cleared your form cache and everything is working fine now. I tested your form and it is working fine now.

Please check and let us know how it worked.

Thank you!