Address already in use

this but is marked as closed but as of 2.15.1 it still exists
ways to reproduce it:
1- edit random host
2- RANDOMLY it starts throwing errors:

nginx  | nginx: [emerg] bind() to 0.0.0.0:80 failed (98: Address already in use)
nginx  | nginx: [emerg] bind() to [::]:80 failed (98: Address already in use)
nginx  | nginx: [emerg] bind() to 0.0.0.0:443 failed (98: Address already in use)
nginx  | nginx: [emerg] bind() to [::]:443 failed (98: Address already in use)
nginx  | nginx: [emerg] bind() to 0.0.0.0:81 failed (98: Address already in use)
nginx  | nginx: [emerg] bind() to [::]:81 failed (98: Address already in use)

there is no definite way of checking what triggers it

nginx is installed as docker compose:

cat docker-compose.yaml  | grep -v '#'
services:

   container_name: nginx
   image: 'docker.io/jc21/nginx-proxy-manager:latest'
   restart: unless-stopped
   environment:
     TZ: Europe/London

   ports:
     - target: 443
       mode: host
       protocol: tcp
     - target: 80
       mode: host
       protocol: tcp
     - target: 81
       published: 81
       mode: host
       protocol: tcp

   volumes:
     - ./data:/data
     - ./letsencrypt:/etc/letsencrypt

sudo docker compose down && sudo docker compose up solves the problem until next time it reappears

there is COMPLETELY NOTHING ELSE on this host running - just lxc container on proxmox and docker compose file for nginx

Start with the supplied docker-compose.yaml and reproduce the failure while checking which process owns ports 80, 443, and 81. Compare a clean docker compose down && docker compose up run with the later failure; done means finding a reliable trigger and confirming the ports remain available across restarts.