How to restore the Edit Response URL of a Google Form?

It seems you cannot restore the URL without the help of the administrator.

The Edit Response URL is of the following format:

https://docs.google.com/forms/d/e/{form_id}/viewform?edit2={response_id}

where you can get form_id by directly accessing the form, but you cannot get your response_id once you close your browser. You can visit the page with Edit Response URL as long as your browser remembers your submission. (If it does, It alerts Confirm Form Resubmission when you visit the page.)

Technically, since Google Forms don't require user login, response_id is probably a hashed string initialized only by some info of your answer, which may not contain your account data of Google. It means you cannot extrapolate the hashed string. (If you can, then other people also can, which means other user could edit your response.)

If you can contact your administrator

The administrator may know your Edit Response URL. Even when s/he doesn't know it, s/he can obtain it by running GAS on the spreadsheet. You can google the process.