Failed to start gunicorn.service: Unit gunicorn.service not found. Ubunto 18.04

I am following this How To Set Up Django with Postgres, Nginx, and Gunicorn on Ubuntu 18.04 guide.

I have created the following file .socket

sudo nano /etc/systemd/system/gunicorn.socket

[Unit]
Description=gunicorn socket

[Socket]
ListenStream=/run/gunicorn.sock

[Install]
WantedBy=sockets.target

I have created the following file .service

sudo nano /etc/systemd/system/gunicorn.service

Original RECOMENDED_FORMATTING-s in the guide

[Unit]
Description=gunicorn daemon
Requires=gunicorn.socket
After=network.target


[Service]
User=sammyRECOMENDED_FORMATTING
Group=www-data
WorkingDirectory=/home/sammyRECOMENDED_FORMATTING/myprojectdirRECOMENDED_FORMATTING
ExecStart=/home/sammyRECOMENDED_FORMATTING/myprojectdirRECOMENDED_FORMATTING/myprojectenvRECOMENDED_FORMATTING/bin/gunicorn \
          --access-logfile - \
          --workers 3 \
          --bind unix:/run/gunicorn.sock \
          myprojectRECOMENDED_FORMATTING.wsgi:application

[Install]
WantedBy=multi-user.target

How I have formatted my own version I had my virtual environment outside of the project folder on the server

[Unit]
Description=gunicorn daemon
Requires=gunicorn.socket
After=network.target

[Service]
User=SERVER_USER
Group=www-data
WorkingDirectory=/home/SERVER_USER/MAIN_PROJECT_FOLDER
ExecStart=/home/SERVER_USER/ven/bin/gunicorn \
          --access-logfile - \
          --workers 3 \
          --bind unix:/home/SERVER_USER/MAIN_PROJECT_FOLDER/MAINAPPLICATION_FOLDER.sock \
          MAINAPPLICATION_FOLDER.wsgi:application

[Install]
WantedBy=multi-user.target

I have also tried leaving these as originally recommended

--bind unix:/run/gunicorn.sock \

Than I have tried to execute the following code

sudo systemctl start gunicorn

error message 1

Failed to start gunicorn.service: Unit gunicorn.service not found.

and I have also tried with 2

sudo systemctl start gunicorn.socket

Error message 2

Failed to start gunicorn.socket: Unit gunicorn.socket is not loaded properly: Invalid argument.
See system logs and 'systemctl status gunicorn.socket' for details.

To solve this, I have tried

• https://stackoverflow.com/questions/40711747/failed-to-start-gunicorn-service-unit-gunicorn-service-not-found This points back to the exact same guide that I am doing except with an older version of linux.
• this is not the same code and not answered https://askubuntu.com/questions/748836/unit-gunicorn-service-failed-to-load-no-such-file-or-directory
• Run: systemctl status gunicorn.socket Result: Warning: The unit file, source configuration file or drop-ins of gunicorn.socket changed on disk ● gunicorn.socket - gunicorn daemon Loaded: error (Reason: Invalid argument) Active: inactive (dead)
• Run: systemctl is-enabled gunicorn.socket Result: enabled
• Run: systemctl is-enabled gunicorn.service Result: Failed to get unit file state for gunicorn.service: No such file or directory