Bests & Worsts Reviews from Amazon

I installed and used Kindle for many years on my Windows pc and Fire tablet. I had a lot of ( non-kindle) problems with the Fire tablet and it currently has issues with charging, I bought a Samsung Galaxy S6 android tablet and installed Kindle via the Google store. However, it had problems accessing the email address I use for Amazon account, so I used another email. Installed fine, but it thinks i am different user so can't access my books. I went to Amazon and logged in. It says I already own kindle and won't let me download and install on new tablet. I won't be using the broken Fire tablet any more. So does that mean I can no longer use Kindle on ANY mobile device????