Can not install Lightroom 6 through proposed channels

I have  bought Adobe Lightroom 6 some time ago and I'm trying to install it to my Win10 (used it already some time ago on another device).

Like proposed in these forums, I downloaded the following file: https://creativecloud.adobe.com/apps/download/lightroom

which  installed Lightroom-Version: 3.4 X64 [ 20200804-0825-1542eef ] (Aug 4 2020)

I joined your 7 days trial to see if I can change the product in the SW, was not possible though.

Can someone tell me how to get the correct installation file which installs my once bought product?

Thank a lot in advance.