Cannot signup because apparently I already have a profile

Hy everybody!
I'm trying to sign up in Jotform and the website says that i have already a profile even if:
1. I've never signed up in jotform yet (it's the very first time in my life i use this website)
2. I'm trying with many different email addresses. Can somebody help me please?
Many thanks! 🙂

Hi Camilla, thank you for contacting us.

I checked your email and found that it is attached to a guest account and has this form so far: http://www.jotformeu.com/form/70142138359353

Perhaps you worked on this form some time in the past, through other services, without realizing it was provided by JotForm?

In any case, if this account and form are yours, we could convert them to a proper account with the username of your preference. Please send us a confirmation reply if that's the case, with 3 usernames by order of preference, just in case your first choice of username is not available. Thank you.