Chat Encryption: Messages fail to decrypt randomly

Has anyone had issues in which chats will just randomly refuse to decrypt for certain users?  Most frequently it happens when someone views/sends a chat on one device and then attempts to view/send it on another device (eg the chat is opened on one's work laptop and that works, but then the user views it on their personal laptop and they can't view the chat).

But sometimes, it happens even when both users involved assure me they're only using one device.  And it seems to strike users at random.  Sometimes chats will fail to decrypt for one person and at no point does the "decryption key become available" no matter what they do--the chats simply fail to display for one person.  It even happens in group chats or channels where one person's messages will not decrypt for everyone else, yet everyone else's messages do.  And sometimes someone will tell me that nobody can view any of their messages, but then I send them a test message and they respond and we can both view each other's messages.  Yet the messages don't display for everyone else they chat with.  So it's a totally random yet persistent occurrence and I have as yet not managed to find a cause.

The way I used to fix this was to delete and re-create the affected user's account.  Which works like a charm, but this means they lose all their chats so many people aren't too happy with that solution.  Zoom Support once provided me with a cleaner.exe file which I can run on someone's computer and then re-install the latest version of Zoom.  This works for the most part, but sometimes we do this on someone's computer, and then a week later, the same encryption issue starts happening again.

So has anyone found a permanent solution for this issue?  And does anyone know the cause?  I wish Zoom would add some kind of functionality to get the encryption working more reliably because it does seem to get stuck for people frequently.