update submission

I assume that you are asking about editing data that is already submitted.

You can edit submissions being made to your forms by going to your Submissions page and clicking on the Edit button on the right.

If you are looking for a way to allow your users to update their own submission at a later date, you can add the Edit Link into your Email Notification / Autoresponders, and the Edit Link will serve the same function.

You can see more details about these methods in the following guides:

http://www.jotform.com/help/325-How-to-Edit-Submissions-Made-on-Your-Forms

http://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date

Please note that you will not be able to update/edit any payment data in an already submitted form, but you will be able to update other data. Please let us know if you need further help or clarifications, we will be happy to assist.