Parallels can't find Windows HD after migration from TimeMachine

I got a new Mac laptop and brought all my files over from the old laptop (including Windows 10 and Parallels 15) via Migration Assistant, using my Time Machine back up. The new laptop has a 4TB hard drive, the old one had a 2TB one.

I've been running for a week now, all apps seem okay, but when I tried running Parallels for the first time, and activated it successfully, it said it couldn't find the hard drive!


I went to Parallel's Settings dialog box, and this is what I see for specifying the hard drive:



What to do? I had a bunch of apps and files there! Ack!

 

I did find a Windows 10.pvm in my user > Documents > Parallels folder. It's 115 MB which seems small to me. Sigh.
I can't figure out how to tell Parallels where my hard drive is. It says I can't make a change while the virtual machine is running, but it opens with Windows overlay saying it's in "Suspend" mode, and I can't shut it down. (Those menu items from Actions are dimmed).

 

Hi @AnneC, yes, your hard drive size is strange.
Do you have any backup copy of your VM?