Screen Time is not allowing me to select from all apps when setting limits

I want to set daily limits on my son's usage of several apps. I want these apps to be limited, let's say to 2 hours a day, as a group. So, if he wants to play Fortnight for an hour and Clash Royale for an hour--fine. If he wants to play Fortnight for 1.5 hours, and Clash Royale for 30 minutes--fine. Then both would be unavailable.

I'm finding this impossible to set up. I'm not able to select every single app I want to for a single limit. Specifically, Fortnight and Clash Royale aren't always both available as apps to add to a limit.

The first problem is that when I create limits using Categories, ie Games and Entertainment, it's not properly identifying which apps are in these categories. Specifically, Fortnight is not included when I set a limit using these categories though it is identified as a Game app.

So, I went about it a different way. From the screen that shows usage for the day, I selected Fortnight, which is displayed along with the amount of time used for the day (which seems incorrect to me, but that's a different story). I am moved to a screen that shows the usage of the app and some info about it. At the bottom of the screen, I clicked Add Limit. I come to the screen that allows you to set up the time limits, and choose "Block at End of Limit." It shows Fortnight as included in this limit, and there's an option for Edit Apps. When I choose Edit Apps, I get a long list of apps and I can individually select which should be part of this time limit. This is exactly what I need, BUT....Clash Royale is not on this list. So, I can't combine those two games into a single limit!

When I try this process by starting with Clash Royale from the screen showing daily usage, I have the same problem--I can limit Clash Royale, but Fortnight is not on the list of available apps to wrap into that limit.

Any ideas?!

Thank you.