Could I switch my email I use to sign in ?

I used a Facebook login but that uses an email I no longer have. Could i switch to a different one? 

You can update it in the Account Profile page. Here's the link: https://www.jotform.com/myaccount/profile

You also need to reset the password by following this guide:

https://www.jotform.com/help/489-How-to-reset-JotForm-account-password

Try it and let us know if you need further help. Thank you.