ecto usage in example projects?

Hi all! I’m new to elixir and phoenix and am trying to run this project:
https://github.com/chvanikoff/reph2

I want to convert an existing react app (or at least the rest api for the database to elixir but every example project I find on Github has some sort or error regarding ecto. I’ve tried all the examples posted in https://forum.elixirforum.com/t/user-authentication-in-phoenix/118/81 but encounter similar errors to this:
could not compile dependency :phoenix_ecto, "mix compile" failed. You can recompile this dependency with "mix deps.compile phoenix_ecto", update it with "mix deps.update phoenix_ecto" or clean it with "mix deps.clean phoenix_ecto"

I’ve tried cleaning all my mix packages as well as mix.update --all.

Are all these projects just dead or am I missing something?

Also if anyone has suggestions of a working example of a elixir server with authentication (ideally with react as well) please do hesitate to share.

Thank you to the elixir developers I can see the magic in the bottle but still feel like I’m taping on the glass.

Thank you for any/all suggestions/ideas/setting me straight