We need a lot more information to help. There are so many different things that could mean. It could mean that you see the apps, but when you launch them, there's a blank screen; it could mean you can launch an app, but it immediately crashes; it could mean the apps don't even show; and so on.
So, what is your Roku device and software version? Settings > System > About
Describe exactly what happens, what you are doing, and what happens along the way.
DBDukes Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution." Note: I am not a Roku employee.