Error when trying to send email in contact form

I have a Mezzanine project hosted in a droplet using smtp.gmail.com as the host. I have a contact form that should send me an email when someone wants to inquire about more information. I get a 500 status code from Nginx when trying to send an email.

Here is when the problem occurs. To produce the problem, I go into my admin page in my Mezzanine project. I go to my Pages, and then select my form page called Contact. Inside this contact form page, I have a few options in the email section. In the from address: I put in a valid email. In the send mail to others: part, I put the same email. That way I am notified when someone sends an inquiry. This is how the problem is produced.

When I leave the send mail to others: part empty, the page works correctly. Although, I don’t get a notification. Here are things I’ve tried:

I have run the python manage.py shell command to attempt sending mail that way, and it does successfully. I have also sent emails correctly when just running on my local machine.

I am assuming there is an issue with my droplets server not allowing outgoing emails? I have run the command: sudo ufw allow 587 and it still doesn’t allow me to send emails. Does anyone know what else I can do to further troubleshoot this issue?