AppleTV app on Amazon FireStick ?

I installed my Apple TV app on my Amazon FireStick TV and it shows in my applications. However, when I click to open, it tells me that my FireStick must be updated in settings. I went to setting and updated, but I am still getting the same error. I went back to setting and it shows that my FireStick is up to date. I restarted my FireTV and I am still getting the same error. I am running a 2015 model of the FireStick.... Is it maybe too old to run AppleTV?