При использовании вашей формы, в конце есть строчка сделано на jotform.Возможно это у�

You must be referring to the "Powered by JotForm" branding on your forms.

You can remove that once you upgrade your subscription to paid plan.

You can review more details here 

https://www.jotform.com/answers/905857-Remove-Powered-by-JotForm-

I also recommend signing up for an account if you haven't yet.

https://www.jotform.com/signup

Thanks.