Copy/paste between Mac and Windows has stopped working in v 20.2.1

Copy/paste has also recently stopped working for me. I've read the various entries in the forum, checked the configuration, reinstalled parallels tools, restarted Windows, restarted my MacBook, uninstalled Avast, and re-downloaded and re-installed Parallels. It still doesn't work. I haven't updated Mac OS in a long time (I'm on Monterey 12.7.6 due to my MacBook model being too old to be updated), so no changes have occurred there, and the problem has to lie with Parallels.