Data directory is readable by other users error with NTFS usb drive on linux

I want to use Nextcloud using an NTFS usb drive connected on a linux PC. I have tried to use NTFS-3G mapping to get the access on this external NTFS drive, seems Nextcloud now is able to write in it but the first configuration stops with this error:

Your data directory is readable by other users

Please change the permissions to 0770 so that the directory cannot be listed by other users.

If I try to run

chmod -R 0770 “/home/myusername/mymountpointfolder”

the problem remains

How can I fix this problem (or force nextcloud to just ignore it if not possible)?