How can the users edit and re-submit their previous submissions?

I have a form that I use for my customers to request invoices

I want them to be able to fill the form once, and the second time they put their names, they can get the fields filled automatically and edit what the need before sending it.

It can be a second form, one for new submitions and a returning

is it possible?

Yes, it's possible. Please follow this guide here https://www.jotform.com/help/40-How-to-Let-Users-Update-Their-Form-Submissions-at-a-Later-Date on how you can add the "Edit link" in your auto responder so that users will receive an email with the edit link.

Let us know if you have any questions or if you need further assistance.