Java Android create file chmod 666

Question

I can't understand why when saving a file the permissions are not set to 666 Tell me what could be the problem?

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
        android:maxSdkVersion="28"/>

java code:

            if (file.exists()) {
                file.delete();
            }

            file.createNewFile();
            file.setReadable(true);
            file.setWritable(true);
            file.setWritable(true, false);
            file.setReadable(true, false);



            Set<PosixFilePermission> crunchifyPermissions = new HashSet<>();
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                crunchifyPermissions.add(PosixFilePermission.OWNER_READ);
                crunchifyPermissions.add(PosixFilePermission.OWNER_WRITE);
                crunchifyPermissions.add(PosixFilePermission.GROUP_READ);
                crunchifyPermissions.add(PosixFilePermission.GROUP_WRITE);
                crunchifyPermissions.add(PosixFilePermission.OTHERS_READ);
                crunchifyPermissions.add(PosixFilePermission.OTHERS_WRITE);
                Files.setPosixFilePermissions(Paths.get(file.getPath()), crunchifyPermissions);
            }
    
            FileWriter writer = new FileWriter(file, true);
            BufferedWriter bufferWriter = new BufferedWriter(writer);
            bufferWriter.append(content);
            bufferWriter.newLine();
            bufferWriter.close();

If I uninstall the app and then install it again. Then, after that, the application does not have access to this file. Despite the fact that I set the rights to 666, they are still set for the user, and not for everyone else.