Unable to Update to v20

I've been running v19.4.1 in Sonoma on an Intel MacBook Pro, which I recently migrated to an M4 Pro Mac mini running Sequoia. I just upgraded Parallels on the MacBook Pro to v20.1.2, but when I click "Install Update" on the Parallels startup screen on the Mac mini it returns:
"Unable to save the file in /private/var/folders/tq/jp_7gnhd6sg5jdmh_m9crs3w0000gn/T.
Please make sure you are allowed to write to this location and try again."

What's going no here and how do I fix, please?

 

Thanks for the reply. I found a solution, which was to ignore the Install Update button in v19 and just download and install v20.
Thanks again.