My account has been hacked?

In about ten minutes, my account is full of 100 responses, all junk. I believe it is due to a virus from your site that pushes users to upgrade their form. please provide a suiable solution.  You nearly crashed our mail-server!

We apologize for the inconvenience, we had a brief issue that made submissions to duplicate. This has been already fixed. I have reset your submissions counter. Your account is available now.

In addition to this, you may enable the unique submissions to prevent multiple submissions: https://www.jotform.com/help/64-How-to-Set-Unique-Submissions-on-a-Form 

Let us know if you need more help.

My query was something different.  The responses I received yesterday were all spam (not duplicate responses).  We had to block the jotform address because of the spam.  Can you tell me the IP address from which the spam responses were submitted?

Beena

I presume your form was used to spam your email address? JotForm mailservers did not spam you, instead, I believe your form was used to submit spam messages. I see there are duplicate submissions in your form titled "IGIB Annual Report 2015-16". May we know if the form is embedded on a website? It is possible that the spammer has seen a security flaw in the website itself that was used to send the spams. 

If you have embedded the form using the full source code in your website, I suggest removing it and re-embed using the iFrame embed code. Another way to prevent spams is to add captcha fields on your form, here's a guide that you can follow: https://www.jotform.com/help/205-How-to-add-a-CAPTCHA-field 

To know the IP address of the submitter, you can check your submissions page, here's a guide that you can follow: https://www.jotform.com/help/31-How-to-Find-IP-Addresses-of-Form-Submitters. From there, you can block them on your website. 

Let us know if that works.