Do the following before contacting customer service:
1. Uninstall the plugin
2. Restart the computer
3. re-install plugin
4. Restart the computer
5. See if you can edit zoom appointment
If the problem still persists do the next steps:
6. Press Window key + R
7. Type "outlook.exe /cleanviews"
8. Press Window key + R
9. Type "Outlook.exe / resetnavpane"
10. See if you can edit zoom appointment
If the problem still persists, I recommend doing the uninstall & reinstall steps above (1-5). If there is still a problem then reach out to customer service. I find clicking the chat icon on the bottom right quicker than calling. Let them know you had done the following steps and see if there have been any solutions other than reaching out to Microsoft.
If Zoom has no other resolution other than the ones above, then your next step is to reach out to Microsoft. I will post details from that conversation too.
My current version of the Zoom/Outlook plug is Version 5.7.6.92.