Uploaded pdf isn't fillable

I uploaded a pdf to the fillable pdf form creator, and received an email stating that it was successfully imported. I clicked on the link to "Download Your PDF," but the PDF that opened is not fillable and when I hit "submit" at the bottom of the form, nothing happens. What do I need to do?

To create a fillable PDF in this manner, the form would need to have been created in Adobe Forms Central.  This application converts fillable PDF forms made using their now shutdown system into fillable PDF JotForm forms.  If the PDF was not created using Adobe Forms Central, it may not properly convert to our format and will likely need to be manually recreated.

We do have another app that can import and PDF, however, what it is able to convert is quite limited:

http://apps.jotform.com/app/spread2jot