If so, are you currently using the FireTV or Android version?
Have you updated the software to the latest version?
At this time, new installs do not work, due to force close (Android version), location issues (even with location enabled), or complete Error 40s (just an issue with the app).
If you are running it without issue, please share details for us fellow users.
So sad that DirecTV Now doesn't have a Android TV version. I'm hoping it comes soon!