Office 2016 MSI version switching to C2R version

Question

I have a Windows 10 22H2 system running Office 2016 msi installer - Volume Licensing. Twice now in the past few weeks my system has automatically switched itself to the C2R version, installing the MS Office Click to Run service, etc. Once this occurs, I'm no longer able to run my Office apps. The first time I had to completely remove Office from the computer, ultimately needing the Microsoft Support and Recovery Assistant tool to uninstall, then reinstall the MSI from the .iso file. This happened again today while using Outlook. Outlook is still running as I type this, but if I close it down, it's toast. I'm unable to start office apps: A window pops up "Updating Microsoft 365 and Office, please wait a moment. Then fails with "application was unable to start correctly (0xc0000142) I don't want the C2R version, I didn't attempt to install it. How can I determine why this is happening and prevent it? Is there anyway to revert this back to the MSI version without a complete reinstall? Thanks,