Hi, you seem to have posted from an Android device, but I will assume that this relates to a Desktop version. You don't need an account to use Firefox, although there are some services that require it, but in any case, that shouldn't create a new Profile. *[[Access Mozilla Services with a Firefox Account]] *[[How do I delete my Firefox Account?]] '''For your missing data, please see''' [[Recover user data missing after Firefox update]] From what you say, this is less likely than the above, but in case a Refresh has occurred, please look on your Desktop for a file named Old Firefox Data - [[Refresh Firefox - reset add-ons and settings]]. *[[Profiles - Where Firefox stores your bookmarks, passwords and other user data]]. *[[Recovering important data from an old profile]]. ''If your question is resolved by this or another answer, please help other users by marking the best reply as Solved. Thank you!''