Hi @David_Shnitkin sorry for being slow to respond and to hear about the loss of access. There’s not a lot we can do for a forgotten master password, without it the encrypted local database can’t be opened. If it’s definitely forgotten, the only option is to reset the installation, deleting all data. For what it’s worth, turning off the Mask switch on the login view can be helpful if you want to try entering variations on what the password might be, if for instance the new password has a typo from what was intended–there’s no limit to the number of login attempts.
Did your wife change her master password recently, by any chance, and if so, would she remember the previous one, and also have used the Sync feature?