Install OnlyOffice 7.2.4 on Debian 11 Bullseye

onlyofficeInstall.sh

#!/bin/bash

##########################################################################
# Tavinus Nov 2022
#
# https://gist.github.com/tavinus/64b89730e8deb5253e66cce3b5a6b21f
# This is a work in progress, use at your own risk
#
# The POSTGRES password is 'onlyoffice' and 
# it will be asked during install
##########################################################################


if [ "$EUID" -ne 0 ]
  then echo "Please run as root"
  exit
fi

# initial setup
apt update
apt upgrade -y
apt install -y sudo nano htop gnupg2

# postgresql
apt install -y postgresql
sudo -i -u postgres psql -c "CREATE DATABASE onlyoffice;"
sudo -i -u postgres psql -c "CREATE USER onlyoffice WITH password 'onlyoffice';"
sudo -i -u postgres psql -c "GRANT ALL privileges ON DATABASE onlyoffice TO onlyoffice;"

# rabbitmq
apt install -y rabbitmq-server

# nginx
apt install -y nginx-extras

# add gpg key
mkdir -p ~/.gnupg
chmod 700 ~/.gnupg
gpg --no-default-keyring --keyring gnupg-ring:/tmp/onlyoffice.gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys CB2DE8E5
chmod 644 /tmp/onlyoffice.gpg
chown root:root /tmp/onlyoffice.gpg
mv /tmp/onlyoffice.gpg /etc/apt/trusted.gpg.d/

# add repo
echo "deb https://download.onlyoffice.com/repo/debian squeeze main" | tee /etc/apt/sources.list.d/onlyoffice.list
apt update

# add ms fonts
apt install -y ttf-mscorefonts-installer

# install only office
apt install -y onlyoffice-documentserver

# Show JWT info
 documentserver-jwt-status.sh
 
 echo
 echo "ALL DONE"
 
 exit 0

Had the same issue as @master-mcfly. After digging into problem i found out that "ds-docservice.service" had errors mentioning "DB table "task_result" does not exist". Also there was nothing running on port 8000.
To fix that:
Set the onlyoffice to be the DB owner sudo -i -u postgres psql -c "ALTER DATABASE onlyoffice OWNER TO onlyoffice;"
Import the schema psql -h localhost -U onlyoffice -d onlyoffice -f /var/www/onlyoffice/documentserver/server/schema/postgresql/createdb.sql
Restart the service systemctl restart ds-docservice.service
The ss -tuln | grep 8000 should now return the doc server listening