Macos catalina Reinstall the system（The computer reinstalls the system for new employees）

I want to reinstall the Macos catalina system through UEM (distribute the computer to new employees).

old Macos catalina is 10.15.5

First, upload the "install Macos catalina 10.15.6" installation package in UEM, the size is 8.3G

And in the deployment script, navigate to the Scripts tab. In Pre-Install Script,

"#!/bin/sh

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/startosinstall --eraseinstall --newvolumename "Macintosh HD" --agreetolicense"

But I found that after the application was released, it did not take effect.

UEM thought that Macos catalina was already installed on the system and prevented the download of the new 10.15.6 installation package to Applications.

Do you have best practices?