failed to saving multiple instance in one form in django admin

I am new to Django and I am trying to create an account form where you select a user and check the platforms you want and it creates an account in the account table for the user with each platform checked.
so :
I have three models: users, platforms, and accounts in the model.py file

class User(models.Model):
    first_name = models.CharField(max_length=255)
    last_name = models.CharField(max_length=255)

class Platform(models.Model):
    platform_name = models.CharField(max_length=255)
    platform_link = models.CharField(max_length=255)

class Account(models.Model):
    platform = models.ForeignKey(Platform, on_delete=models.PROTECT)
    user = models.ForeignKey(User, on_delete=models.PROTECT)

I then created an AccountForm class

class AccountForm(ModelForm):
    platforms = forms.ModelMultipleChoiceField(widget=forms.CheckboxSelectMultiple(), queryset=Platform.objects.all())

    class Meta:
        model: Account
        fields = ["user", "platforms"]
        widgets = {'platform': forms.HiddenInput()}

in the admin.py

class AccountAdmin(admin.ModelAdmin):
    list_display =  ["id", "platform", "user"]
    form = AccountForm
  
    
    def save_form(self, request: Any, form: Any, change: Any) -> Any:  
        platforms = form.cleaned_data["platforms"]
        if platforms:
            accounts_to_save = []
            for platform in platforms:
                account = form.save(commit=False)
                form.instance.platform = platform
                accounts_to_save.append(account)
            
            Account.objects.bulk_create(accounts_to_save)
        else:
            return super().save_form(request, form, change)
        return super().save_form(request, form, change)
    

I tried iterating through the checked platforms and saving each time, but it keeps saving the instances with only the last value of in the platforms list. so if we select user 2 and checked platform 1 and platform 2 >> it saves [(user 2, platform 2) ,(user 2, platform 2) ] instead of [(user 2, platform 1) ,(user 2, platform 2) ]

The problem was that the form sent in the last return super.save_form must be filled.

I ended up iterating through my platforms and creating the accounts with objects.create, and left the last one to be the one sent in the form so that the form sent in the super method isn't empty.

def save_form(self, request: Any, form: Any, change: Any) -> Any:  
    platforms = form.cleaned_data['platforms']
    if platforms:
        for p in platforms[:len(platforms)-1]:
            Account.objects.create( platform= p ,user=form.cleaned_data['user'])
        form.instance.platform = platforms[len(platforms)-1]
    return super().save_form(request, form, change)

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