nextclouddb not accepting configured passwords?

I have just done a fresh install of OMV5 and I am in the process of setting up Nextcloud via Docker. I have followed this guide https://forum.openmediavault.o…g-omv-and-docker-compose/and I have the containers set up and working. The problems began when I opened Nextcloud for the first time and tried to configure the database:

Error while trying to create admin user: Failed to connect to the database: An exception occurred in the driver: SQLSTATE[HY000] [1045] Access denied for user 'root'@'nextcloud.nextcloud_default' (using password: YES) 

Now I did the initial install with these settings in docker-compose.yml:

    environment:
      - PUID=1001 #change PUID if needed
      - PGID=100  #change PGID if needed
      - MYSQL_ROOT_PASSWORD=mypasshere

But it did not work. I then tried to run mysql -u root -p inside the container as per these instructions RE: Nextcloud with Letsencrypt using OMV and docker-compose - Q&A but it just kept saying "ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)" even though the password was most definitely correct. I verified the password in the container settings and it was correct.

I googled some more and found this thread RE: Nextcloud with Letsencrypt using OMV and docker-compose - Q&A which has a post saying to set up mariadb with these parameters:

- MYSQL_DATABASE=nextcloud
- MYSQL_USER=nextcloud
- MYSQL_PASSWORD=secretpassword

So I changed those in docker-compose.yml, (in order to rule out locale issues I tested this with just secretpassword) ran docker-compose up -d but I am still having the same problem with the Nextcloud setup and I still can't access the database via CLI.:

root@39142896bec1:/# mysql -u nextcloud -p
Enter password: (TRIED PUTTING SECRETPASSWORD HERE)
ERROR 1045 (28000): Access denied for user 'nextcloud'@'localhost' (using password: YES)

This is not making any sense, it seems that for some reason the user settings for mariadb are being ignored and I therefore can't access the database. There are no errors in the nextclouddb container logs and the config looks ok:

What on earth could be the problem?

Here is my docker-compose:

version: "2"
services:
  nextcloud:
    image: ghcr.io/linuxserver/nextcloud
    container_name: nextcloud
    environment:
      - PUID=1001 #change PUID if needed
      - PGID=100  #change PGID if needed
      - TZ=Europe/Helsinki
    volumes:
      - /srv/dev-disk-by-uuid-7763fbc8-15ec-4b11-b010-417a5aaec284/appdata/nextcloud/config:/config
      - /srv/dev-disk-by-uuid-7763fbc8-15ec-4b11-b010-417a5aaec284/appdata/nextcloud/data:/data
    depends_on:
      - mariadb
#    ports: # uncomment this and the next line if you want to bypass the proxy
#      - 450:443
    restart: unless-stopped
  mariadb:
    image: ghcr.io/linuxserver/mariadb
    container_name: nextclouddb
    environment:
      - PUID=1001 #change PUID if needed
      - PGID=100  #change PGID if needed
      - MYSQL_ROOT_PASSWORD=passwordedited
      - TZ=Europe/Helsinki
    volumes:
      - /srv/dev-disk-by-uuid-7763fbc8-15ec-4b11-b010-417a5aaec284/appdata/nextclouddb:/config
    restart: unless-stopped
  swag:
    image: linuxserver/swag
    container_name: swag
    cap_add:
      - NET_ADMIN
    environment:
      - PUID=1001 #change PUID if needed
      - PGID=100  #change PGID if needed
      - TZ=Europe/Helsinki
      - URL=domainedited.no-ip.org
      - SUBDOMAINS=,
      - VALIDATION=http
      - EMAIL=emailedited@gmail.com
    volumes:
      - /srv/dev-disk-by-uuid-7763fbc8-15ec-4b11-b010-417a5aaec284/appdata/swag:/config
    ports:
      - 444:443
      - 81:80
    restart: unless-stopped

And here is what I enter in the Nextcloud welcome screen:

Eh I noticed just now that my OMV OS drive was 100% full, which was probably causing the issue with accessing the database. And yes I used "passwordedited" as password.

/var/lib/docker/overlay2 was for some reason taking in excess of 27 gigabytes even though this is a fresh OMV install and so far I have only installed the Nextcloud and Swag containers. I have no idea why it was taking up so much space.

In any case, I did a docker system prune --all which cleared all the extra stuff, after which I stopped and removed the running containers and deleted the appdata -folder.

...and that finally did the trick, now I was able to finish the Nextcloud install :). Thank you for the assistance!