Most of my passwords have disapeared from settings

i realised that 140 passwords have been deleted from my settings in the browser, only 6 random one have been left. i had not asked or clicked on a browser update. I have tried to find the loginData in brave browser file, with no luck. When i go to a know site, the login field is left empty when it used to
load passwords.
How can i retrieve my lost passwords ? i am wondering if i have been hacked or if it is a bug in the browser.