rsync doesnt copy permissions to external drive

a similar Q is asked here: https://unix.stackexchange.com/questions/229779/rsync-command-not-preserving-permissions. They suggest using sudo, but sudo makes no difference for me

the command i'm running is: rsync -avxPnh --itemize-changes --out-format="%i|%n|" --update --delete [source directory] [destination directory]'

-a: archive, preserves permissions, but I can see from --itemize-changes that the difference between files in the two directories is the permissions (and nothing else)

the external drive shows full permissions (drwxrwxrwx) on everything. It is a datalocker DL3.

because the permissions differ on the laptop versus external hard drive, the sync is generating a long list of changes every time i sync. Is it the fault of rsync or the external drive?

edit: the datalocker DL3 "comes preformatted with the Windows NTFS file system. All major file systems are supported (HFS, NTFS, EXT, FAT). ... [it] is completely cross-platform compatible and OS agnostic. With no software or special drivers required, the DL3 works with Windows, Linux, MacOS, Android phones and tablets, Chromebooks, and embedded systems - any system that can utilize USB Mass Storage." https://support.datalocker.com/support/solutions/articles/4000076369-dl3-dl3-fe-user-manual I'm using ubuntu 18.04 and have never had any issue using the datalocker DL3

as someone noted - permissions are lost because the external drive is using a different file system. Adding --no-p (after -a) will stop the changes being flagged, this seems the simplest solution

note that archive (-a) implies: -rlptgoD, and from the rsync man page:

" --no-OPTION: You may turn off one or more implied options by prefixing the option name with "no-". Not all options may be pre‐fixed with a "no-": only options that are implied by other options (e.g. --no-D, --no-perms) or have different defaults in various circumstances (e.g. --no-whole-file, --no-blocking-io, --no-dirs). You may specify either the short or the long option name after the "no-" prefix (e.g. --no-R is the same as --no-relative).

For example: if you want to use -a (--archive) but don’t want -o (--owner), instead of converting -a into -rlptgD, you could specify -a --no-o (or -a --no-owner). The order of the options is important: if you specify --no-r -a, the -r option would end up being turned on, the opposite of -a --no-r. Note also that the side-effects of the --files-from option are NOT positional, as it affects the default state of several options and slightly changes the meaning of -a (see the --files-from option for more details)."