a few more information about the issue whould be great.
Are you trying to install LabVIEW out of the already installed NI Package Manager or from a downloaded executable?
Is it the offline Installer? Where have you downloaded your Installer?
Have you tried to install out of the already installed NI PAckage Manager?
But there should be a different error message than.
And the answer to my other questions?
This issue happens when a higher version of VI Package Manager is already installed which was directly downloaded from https://www.vipm.io/download/. You can avoid this by unchecking JKI VI Package Manager during installation
This issue has been resolved in LabVIEW 2021+ installers and there is no need to uncheck this even if there is a higher version of VIPM is already installed.