I just fixed mine with the same problem! I could not get the remote to operate the firestick and unfortunately the Wifi was not connected yet so I could not yet use my phone App.
Turned out my remote was not working.
Here is how to work around it:
I borrowed another remote to get the firestick online.
How to Pair a new remote to a firestick:
So you get to the input/screen on your tv where you can view the firestick.
Make sure to put in fresh new batteries in the new/borrowed remote or you might deive yourself crazy!
1. unplug the power to the fire stick. Wait 10seconds
2. Re-plug the power to the firestick. Watch the firestick boot up on your screen
3. Press select (middle round button) and home button at the same time - I had to hold mine for 45 seconds; I got a message that a new remote was connected!
Then you can get your firestick online with Wifi - then just start using your phone