If you lost your logins and have no written backups of them there nothing much anyone can do since no one here knows who is who and they have no access to your computer or Firefox account sync.

You need a backup copy of logins.json (encrypted logins) and key4.db (encryption key) to recover lost logins.\ *https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data *https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update You can look at a utility to browse System Restore points to see if you have an earlier copy of logins.json and key4.db. *https://www.shadowexplorer.com/ *https://www.nirsoft.net/utils/shadow_copy_view.html