Virtual Background Freezing when selected on Mac running OS 12.6

Had to replace my HD in my iMac and now Zoom backgrounds won't work. Running OS 12.6.5 Montery on a 4GHz quad-core Intel Core i7 iMac. Every time I try to select a background, Zoom freezes. Can't use my custom backgrounds, can't blur, etc. Camera works fine in Google Meet and FaceTime. I've uninstalled Zoom several times and have the latest version. I also get the 'background not loading' error message and have to cancel loading a background. Is there a fix for this please? It was working just a few months ago.