Error - the installer is too old to be opened on this version of macOS- Catalina

Hello ,

I am trying to install the earlier version macOS Catalina. However it's gving this error- the installer is too old to be opened on this version of macOS. Please help me how to overcome this error??

Currently macOS big Sur is installed, but some my applications does not work. so I want to move back to macOS Catalina.

Kind Regards,

sandeep