Adding a Feat instead of an ability score impovement

My character has leveled up to a 4th Level Wizard. Rather than take an ability score improvement I want to take a feat, but the user interface won't give me the choices of feats available.

Am I missing something? 

You should see something like this:

and if you select Feat, a dropdown will appear below it for the options.

Note that only Grappler is available if you are using the Basic Rules only and haven't bought anything else or don't have anything content shared.

I'm getting something similar. It will allow me to choose feat but the dropdown menu for feats does not appear