Technical support at my host eventually helped me. by allowing access. I was getting the following error…
Form Designer needs your help!
Your web server thinks that Form Designer is an unwelcome script. Obviously, it’s not.
For Form Designer to work, you need to contact your web host and request that they “whitelist your domain for ModSecurity.” This shouldn’t pose any risk to your website; it just lets the host know you want the Form Designer to do what it does best!
Good luck with it