macOS TV App Home Videos disappear from App after being imported
I have imported a tremendous amount of home videos to a fresh install of macOS Catalina (version 10.15.7) on my iMac (27-inch, Late 2013). The movies appear in the TV App under Home Videos. Several days later, I try to watch the home videos, and the last imported videos no longer show up. If I go into the Movies\TV\Home Videos directory, the .m4v files are there, but they don't show up in the TV App.
I can re-import the Home Videos. A duplicate copy is moved to the Movies\TV\Home Videos directory with _1.m4v extension and will show up in the TV App for a period of time and then disappear again.
One item to note. I have the operating system on a 500GB SSD internal drive. The Videos are located on a 3TB internal HDD.
Is there a way to re-index? Are there other troubleshooting steps I can take?
Please note that this hardware only allows Catalina as the latest version of OS, so I cannot upgrade the OS.
iMac, OS X 10.11