Unable to deploy phoenix with edeliver which throws an compile_env/4 error

Question

I am trying to deploy the app with edeliver. However during the .... I get the following error. Not sure what is it actually means. Though in the dev environment it works fine.

1. mix compile - Successful
2. iex -S mix phx.server - I can serve the api and no issues.
3. Guardian can also authenticate the JWT token

So puzzled about deployment.

Building the code for edeliver

mix edeliver build release --verbose

Error:

    == Compilation error in file lib/pxf/auth/guardian.ex ==
    ** (FunctionClauseError) no function clause matching in Application."MACRO-compile_env"/4    
        
        The following arguments were given to Application."MACRO-compile_env"/4:
        
            # 1
            #Macro.Env<aliases: [], context: nil, context_modules: [Pxf.Auth.Guardian], file: "/tmp/edeliver/pxf/builds/lib/pxf/auth/guardian.ex", function: nil, functions: [{Kernel, [!=: 2, !==: 2, *: 2, +: 1, +: 2, ++: 2, -: 1, -: 2, --: 2, /: 2, <: 2, <=: 2, ==: 2, ===: 2, =~: 2, >: 2, >=: 2, abs: 1, apply: 2, apply: 3, binary_part: 3, bit_size: 1, byte_size: 1, ceil: 1, div: 2, elem: 2, exit: 1, floor: 1, function_exported?: 3, get_and_update_in: 3, get_in: 2, hd: 1, inspect: 1, inspect: 2, is_atom: 1, is_binary: 1, is_bitstring: 1, is_boolean: 1, is_float: 1, is_function: 1, is_function: 2, ...]}], lexical_tracker: #PID<0.647.0>, line: 2, macro_aliases: [], macros: [{Kernel, [!: 1, &&: 2, ..: 2, ..//: 3, <>: 2, @: 1, alias!: 1, and: 2, binding: 0, binding: 1, def: 1, def: 2, defdelegate: 2, defexception: 1, defguard: 1, defguardp: 1, defimpl: 2, defimpl: 3, defmacro: 1, defmacro: 2, defmacrop: 1, defmacrop: 2, defmodule: 2, defoverridable: 1, defp: 1, defp: 2, defprotocol: 2, defstruct: 1, destructure: 2, get_and_update_in: 2, if: 2, in: 2, is_exception: 1, is_exception: 2, is_nil: 1, is_struct: 1, is_struct: 2, ...]}], module: Pxf.Auth.Guardian, requires: [Application, Guardian, Kernel, Kernel.Typespec], ...>
        
            # 2
            {:the_otp_app, [line: 2, counter: {Pxf.Auth.Guardian, 2}], Guardian}
        
            # 3
            [{:__MODULE__, [line: 2, counter: {Pxf.Auth.Guardian, 2}], Guardian}, :permissions]
        
            # 4
            nil
        
        (elixir 1.12.2) lib/application.ex:505: Application."MACRO-compile_env"/4
        (elixir 1.12.2) expanding macro: Application.compile_env/2
        lib/pxf/auth/guardian.ex:2: Pxf.Auth.Guardian (module)
        (elixir 1.12.2) expanding macro: Kernel.||/2
        lib/pxf/auth/guardian.ex:2: Pxf.Auth.Guardian (module)
        (elixir 1.12.2) expanding macro: Kernel.@/1
        lib/pxf/auth/guardian.ex:2: Pxf.Auth.Guardian (module)
        (guardian 2.3.1) expanding macro: Guardian.__using__/1

This is a previous project which was build with Phoenix 1.3.2 and I've migrated to Phoenix 1.6.15.

I'm new to this edeliver deployment and not sure whether it is the current way to push the code to the server?