Internal Server Error after start docker from scratch

🚧 Installation
#1

Start a new docker container compose:

version: '2'
volumes:
  nextcloud:
  db:

services:
  db:
    image: postgres
    restart: always
    volumes:
      - m:/DOCKER/nextcloud/postgresql:/var/lib/postgresql/data
    environment:
      - POSTGRES_PASSWORD=pass
      - POSTGRES_DB=nextcloud
      - POSTGRES_USER=nextcloud

  app:
    image: nextcloud
    restart: always
    ports:
      - 80:80
    links:
      - db
    volumes:
      - m:/DOCKER/nextcloud/data:/var/www/html
    environment:
      - POSTGRES_PASSWORD=pass
      - POSTGRES_DB=nextcloud
      - POSTGRES_USER=nextcloud
      - POSTGRES_HOST=db
      - NEXTCLOUD_ADMIN_USER=admin
      - NEXTCLOUD_ADMIN_PASSWORD=admin123

Here is photo I get when docker is up: Imgur: The magic of the Internet
Here is photo of logs from container: Imgur: The magic of the Internet