Problem starting Gunicorn Web Service using Systemd

I have a problem running a Gunicorn Web service using Systemd.

Here are the files I created in order to execute:

The shell script file (/home/ubuntu/mata.sh):

Here's my .service file (/lib/systemd/system/mata.service):

Running the shell script on its own works well, but when running systemctl status mata.service, I am getting the following message:

Any idea?