Django modelformset_factory() adding field manually in views - django

Question

Disclaimer: I am new at Django so I'm sure my code is ugly.
Problem:
My current Model is built as follows:
class person(models.Model):
email = models.EmailField()
date = models.DateField()
phone_number = models.IntegerField()
name = models.CharField(max_length = 50)
belongs_to_group = models.ForeignKey(Group, related_name='group', on_delete=models.SET_NULL, null=True)
belongs_to_user = models.ForeignKey(User, related_name='user', on_delete=models.SET_NULL, null=True)
I have built a modelformset_factory for this using the following code:
personModelFormset = modelformset_factory(
person,
fields=('email', 'date' , 'phone_number', 'name'),
extra=1)
This makes the fields the form renders in the HTML email, date , phone_number, and name. This means that to successfully save the form to the database, I need to also add the fields belongs_to_group and belongs_to_user manually since the website user shouldn't be able to edit these (they should be automatically generated).
Attempted Solution:
To try to do this, I used the following view:
def classes(request):
#add form creation method here
user = request.user
group = value #taken from another form
if request.method == 'POST':
form_2 = personModelFormset (request.POST)
if form_2.is_valid():
for form in form_2:
form.belongs_to_group = value
form.belongs_to_user = user
form.save()
return redirect('home')
But this does not append the information to the form. This method works for me in a normal modelform, so I think I'm not using the modelformset_factory correctly. Does anyone know how I should correctly append the "behind the scenes" model fields to the formsetfactory? Thank you!