File picker forgets last location (always uses home folder) and can’t access recent folders

In all apps, when I summon the “File, Open” dialog (file selector, file picker), it is supposed to open with the last location accessed. But instead, it is always opening at my home folder. Also, any clicks of “Recent Places” fail (instead of opening the clicked directory, they just open the home folder). This wastes a lot of time when I need to open (or upload) multiple files, and it frustrates me every day. Apple had me run many tests for several hours a day over several months, and they eventually gave up and said to wipe my Mac, reinstall macOS, and rebuild my machine manually from scratch. This week I invested five full-time days doing so, and just as I was nearly finished doing so, the bug has now randomly reappeared. MacBook Pro running macOS 14.5 Sonoma. Bug does not occur when I create a new user admin account. In searching the web, I see other people complaining about this, but I do not find a solution. Any help, ideas?