Unusually large snapshots

I'm running Parallels 16 on MacOS Catalina, with Windows 10 as the guest OS. I've noticed lately that the amount of disk space used by Parallels seems excessive. In addition to sucking up a lot of disk space, this also leads to very large backups. In Finder, my Windows 10.pvm file is 144 GB. Virtually the entirety of that seems to be snapshots. I tried using the snapshots manager in Parallels to delete old snapshots, but each time I delete a snapshot, it just seems to compress the data into one of the remaining snapshots. There is always one snapshot of > 120 GB. Here is the complete contents of the Windows 10-0.hdd directory within the .pvm file.



Is there some way to trim down that single large snapshot? These two snapshots of 123 GB and 21 GB seemed to comprise nearly the entire 144 GB of my virtual machine, so I'm guessing they aren't "just" snapshots.

 

Here's the image that didn't seem to come through in the previous post.