I recently purchased a year long lightroom license and when I try to install it I get a message that says Trial ended. How to I install the program or add a license number? Where would I find my license number?

I had a month long trial of Lightroom and I decided to purchase a prepaid 12month Lightroom/Creative Cloud license. When I uninstall Lightroom and then reinstall it, I get a message that says trial ended with the option to 'buy'. How do I install the purchased year long license to my desktop or add a license number? Also wondering where I might find this number?

Thanks