The funny thing is with this email no error appears but the emai is not sent as expected. If the receiver’s email is from gmail the email sents, but in office it doesnt.
If I change the email from settings.py to another emails of mine like email@example.com the error from above appears. Something is really weird here.
As you move into production make sure you have the email authentication setup and tested.
I highly recommend using a transactional email service provider. These types of platforms offer email service geared towards notification type email delivery. There is a popular project called Anymail that makes it straightforward to use a transactional email service provider