Samba write operation can’t be completed because it isn’t supported

I have a server with Ubuntu 18.10. It has docker and docker-compose installed. I have this docker-compose recipe to run samba

version: "3.7"

services:

  samba:
    image: dperson/samba
    container_name: samba
    restart: always
    network_mode: host
    environment:
      TZ: 'America/Argentina/Buenos_Aires'
      WORKGROUP: "WORKGROUP"
      NMBD: "true"
      USERID: "1001"
      GROUPID: "1001"
    command: '-u "$SAMBA_USER;$SAMBA_PASSWORD" -s "media;/media;yes;no;no;myuser;myuser;myuser;myuser"'
    stdin_open: true
    tty: true
    ports:
      - 139:139
      - 445:445
    volumes:
      - /usr/share/zoneinfo/America/Argentina/Buenos_Aires:/etc/localtime
      - $SAMBA_MEDIA:/media

I also have a mac, and I am able to connect to the server with finder, see the files and open them. But when I try to copy or delete a file I get this message

The operation can’t be completed because it isn’t supported.