Identity Pool not configured message shown while Signing In using Amplify-Android using Custom Sign In

Question

I am able to Sign In, using custom authentication using the Amplify API, but in logs it is showing me an Identity Pool error, when I try to fetch the session.

I am getting an Identity Pool error saying: cause=SessionError(exception=ConfigurationException{message=Identity Pool not configured., cause=null, recoverySuggestion=Please check amplifyconfiguration.json file.}

This error can be seen on running:

    fun checkUserExistsHandler() {

        Amplify.Auth.fetchAuthSession(
            { result: AuthSession ->
                Log.i(
                    "AmplifyFetchAuthSession",
                   result.toString()
                )
                

            }
        ) { error: AuthException ->

            Log.e(
                "AmplifyFetchAuthSession",
                error.toString()
            )
        }

    }

Here is my amplifyconfiguration.json I am using CUSTOM_AUTH method for signing in.

{
  "auth": {
    "plugins": {
      "awsCognitoAuthPlugin": {
        "IdentityManager": {
          "Default": {}
        },
        "CognitoUserPool": {
          "Default": {
            "PoolId": "pool-id",
            "AppClientId": "client-id",
            "Region": "Region"
          }
        },
        "Auth": {
          "Default": {
            "authenticationFlowType": "CUSTOM_AUTH"
          }
        }
      }
    }
  }
}```

Even after sign in is successful the Log is shown as

AWSCognitoAuthSession(isSignedIn=true, identityIdResult=AuthSessionResult{value=null, error=ConfigurationException{message=Could not retrieve Identity ID, cause=null, recoverySuggestion=Cognito Identity not configured. Please check amplifyconfiguration.json file.}, type=FAILURE}, awsCredentialsResult=..... ```

What changes should I make, to resolve the error ?