Flutter never asks for any storage permission

So I was using the open_file library to open some pdf files. When I switched from cache storage to app’s local document folder storage using getApplicationDocumentsDirectory(), the files were not opening. Using

var result = await OpenFile.open(filePath);
print(result.message);

return Permission denied: android.permission.MANAGE_EXTERNAL_STORAGE

My filePath is in the format /data/user/0/com.example.<app name>/app_flutter/New-Note-2024-09-19-00-02-48.pdf

It is a bit strange that I need permission to access my app’s local storage

Nevertheless I included

<manifest xmlns:android="http://schemas.android.com/apk/res/android">

    <uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"/>
    
    <application
     ....
</manifest>

In my AndroidManifest.xml, and here is my flutter code for requesting permissions:

   Future<void> requestStoragePermission() async {
      if (await Permission.storage.request().isGranted) {
        // Permission granted
      } else {
          openAppSettings();
        // Handle permission denied
        print("Storage permission denied");
      }
    }

However it defaults automatically to "Permission denied" without me even doing anything.

And if I go to app settings, it shows "No permissions requested" and outputs No permissions found in manifest for: []15.

I even tried including READ_EXTERNAL_STORAGE and WRITE_EXTERNAL_STORAGE on my manifest, still doesn’t work.