Cannot open Trados file by double-clicking after upgrading from Trados 2017 freelance to Trados 2021 freelance

I upgraded my Trados 2017 freelance to Trados 2021 freelance. I deleted all my Trados 2017 files and restarted my computer.

I found that all of my sdlxliff files are shown in the default document icon instead of the Trados icon, and if I double-click on an sdlxliff file, it doesn't open directly (the pop-up shows up asking me to choose an app to open the file). But if I open Trados 2021 and use the Open File option, I can select an sdlxliff file and open it. How do I fix this? Thank you.