GitLab Code Suggestions Doesn't Do Anything

I recently watched GitLab’s webcast about GitLab Duo and was excited to hear about the availability of the code suggestions feature. I’ve installed the GitLab extension in Visual Studio 2022 and provided it with our GitLab instance’s URL and a PAT. There is now a GitLab code suggestions button in Visual Studio’s status bar which I toggle on and off.

However, I’m not seeing any evidence that the extension is actually doing anything. I certainly don’t get any code suggestions. I don’t see any errors anywhere either. I’m writing in C# and I’ve tried some of the suggested ways to get code suggestions, but nothing ever happens.