Hi,
I’m new to Elixir and Phoenix. I recently came across to work on a phoenix project (ver 1.3) developed for an API and now the company wanted to update the framework to 1.6.15 and I’ve managed to do necessary changes to the code. I’ve used this link https://phoenixdiff.org/?source=1.3.0&target=1.6.15 to convert.

However when I compile and serve the application it throws an error regarding the Guardian.

iex -S mix phx.server

Compilation error in file lib/pxf/coll/submission_controller.ex ==
** (CompileError) lib/pxf/coll/submission_controller.ex:3: module Guardian.Phoenix.Controller is not loaded and could not be found. This may be happening because the module you are trying to load directly or indirectly depends on the current module
    (elixir 1.14.2) expanding macro: Kernel.use/1
    lib/pxf/coll/submission_controller.ex:3: Pxf.Web.SubmissionController (module)

I been stuck in this issue for few days already and can’t find the way to get past this problem.

thanks
regards