error

/Users/saurabhnanda/projects/vl-gitlab/haskell/src/Try2.hs:25:13: error:
    • Couldn't match type ‘auth’ with ‘auth1’
      ‘auth’ is a rigid type variable bound by
        the instance declaration
        at /Users/saurabhnanda/projects/vl-gitlab/haskell/src/Try2.hs:24:10-27
      ‘auth1’ is a rigid type variable bound by
        the type signature for:
          getEnv :: forall auth1. AppM auth (Env auth1)
        at /Users/saurabhnanda/projects/vl-gitlab/haskell/src/Try2.hs:25:13-48
      Expected type: AppM auth (Env auth1)
        Actual type: AppM auth (Env auth)
    • When checking that instance signature for ‘getEnv’
        is more general than its signature in the class
        Instance sig: forall auth. AppM auth (Env auth)
           Class sig: forall auth1. AppM auth (Env auth1)
      In the instance declaration for ‘HasEnv (AppM auth)’
   |
25 |   getEnv :: forall auth . (AppM auth) (Env auth)
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Try2.hs

{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE InstanceSigs #-}
{-# LANGUAGE RankNTypes #-}

module Try2 where


import Control.Monad.Reader
import System.Log.FastLogger

data Env auth = Env
  { envLogger :: FastLogger
  , envAuth :: auth
  }

class (Monad m, MonadIO m) => HasEnv m where
  getEnv :: m (Env auth)


type AppM auth = ReaderT (Env auth) IO

instance HasEnv (AppM auth) where
  getEnv :: forall auth . (AppM auth) (Env auth)
  getEnv = ask