All of the Sudden I can't add recipients to my form.

I went to update the email addresses for a form's recipients and I was unable to add anyone.  It they asked that I upgrade my account but that feature was not even on the list. Can you please help?

There has been a recent update on the number of recipients for the Free accounts. The free accounts are now limited to add only one recipient email per email Notification. 

If you want to sent the email Notification to multiple recipients, you will have to create multiple email Notifications, one for each recipient. 

Setting up Email Notifications

Or you can upgrade your account to use this feature.