Cannot add fields to a form

I have been trying to add new fields to an exiting form. I can drag and drop the fields into the form where I want them, edit the field names, etc. but when I access the application, they are not there. I have tried this with a variety of field types and none get saved to the form. I am able to changing the titles of existing fields. I thought it might be a temporary problem, but it has persisted for nearly a week. I wrote to the support email address, but have not received a reply. The application has been modified to share with support. Please advise!