You mean you upgraded across the v27/v28 boundary, and all your plugins went away? Or do you mean something else?Everything disappear with U22
That specific upgrade is known to do that, as a consequence of the Qt5/6 boundary that corresponds to those versions of OBS. Plugins made for OBS v27 and before, and thus Qt5, are not compatible with Qt6, and thus OBS v28 and later. So they'll fail to load. Because they fail to load, and because OBS overwrites all the settings when it closes, it wipes out the settings that they used to have, even if you downgrade back to what it was.
I really wish OBS itself would have put up a big warning about crossing that boundary, and offered a way to preserve the plugin settings if not the plugins themselves. But it didn't. So people don't think anything special until they see that they've lost all of that, by which time it's too late to recover.
If you know, then you can back up everything explicitly (screenshot if necessary), update the plugins too, and put it all back afterwards. But you have to know, and OBS itself completely failed what I consider to be a responsibility to tell you.
(Still remember that it's free, and both made and supported by volunteers. Nothing is guaranteed like a commercial product is.)