Indigo Domotics

I ran across this article today which is up-to-date with the instructions specific to various Fire models... I know a couple of you were having trouble with installation and/or notifications... might be worth factory resetting the Fires in question and running through these instructions. These have the exact version numbers they installed which they claim are working fine just in case your previous (non-working) installs used different versions that for whatever reason seemed to work but didn't.

https://www.androidpolice.com/2019/07/25/install-play-store-amazon-fire-tablet/

Adam