A voting site with Django

----------------------------Model----------------------------------------
class Voter(models.Model):
    gender_type = (('male', 'Male'), ('female', 'Female'))
    admin = models.OneToOneField(CustomUser, on_delete=models.CASCADE)
    gender = models.CharField(max_length=10, choices=gender_type)
    country_region = models.CharField(max_length=255, choices=Countries.choices, default=Countries.Pakistan)
    phone = PhoneNumberField(blank=True, unique=True)
    otp = models.CharField(max_length=10, null=True)
    verified = models.BooleanField(default=False)
    voted = models.BooleanField(default=False)
    otp_sent = models.IntegerField(default=0)  # Control how many OTPs are sent
    ip_address = models.GenericIPAddressField(unique=True, default='ABC')


    def __str__(self):
        return self.admin.first_name


class Position(models.Model):
    ACTIVE = 0
    INACTIVE = 1

    status_choice = ((ACTIVE, 'Active'), (INACTIVE, 'Inactive'))
    name = models.CharField(max_length=50, unique=True)
    max_vote = models.IntegerField()
    priority = models.IntegerField()
    description = models.TextField(null=True, blank=True)
    status = models.PositiveBigIntegerField(default=0, choices=status_choice)

    def __str__(self):
        return self.name


class Candidate(models.Model):
    fullname = models.CharField(max_length=50)
    photo = models.ImageField(upload_to="candidates")
    bio = models.TextField()
    position = models.ForeignKey(Position, on_delete=models.CASCADE, related_name='candidates')

    def __str__(self):
        return self.fullname

    def modify_points(self, added_points):
        self.points += added_points
        self.save()


class Votes(models.Model):
    voter = models.ForeignKey(Voter, on_delete=models.CASCADE)
    position = models.ForeignKey(Position, on_delete=models.CASCADE, related_name='positions')
    candidate = models.ForeignKey(Candidate, on_delete=models.CASCADE, related_name='votes')


class BlockIP(models.Model):
    voter = models.ForeignKey(Voter, on_delete=models.CASCADE, related_name='ip')
    position = models.ForeignKey(Position, on_delete=models.CASCADE, related_name='positions_ip', null=True, blank=True)
    ip_address = models.GenericIPAddressField(default='abc')


@receiver(post_save, sender=Voter)
def default_to_non_active(sender, instance, created, **kwargs):
    if created:
        instance = BlockIP.objects.create(voter=instance, ip_address=instance.ip_address)
        instance.save()

-------------------------------------------- End of model-----------------------------------

def submit_ballot(request):
    if not request.user.is_authenticated:
        return redirect(reverse('index'))

    if request.method != 'POST':
        messages.error(request, "Please, browse the system properly")
        return redirect(reverse('index'))

    # Verify if the voter has voted or not
    voter = request.user.voter
    blocked = BlockIP.objects.filter(voter=voter)
    if voter.voted and blocked:
        messages.error(request, "You have voted already")
        return redirect(reverse('index'))

    form = dict(request.POST)
    form.pop('csrfmiddlewaretoken', None)  # Pop CSRF Token
    form.pop('submit_vote', None)  # Pop Submit Button

    # Ensure at least one vote is selected
    if len(form.keys()) < 1:
        messages.error(request, "Please select at least one candidate")
        return redirect(reverse('index'))
    positions = Position.objects.all()
    form_count = 0
    for position in positions:
        max_vote = position.max_vote
        pos = slugify(position.name)
        pos_id = position.id
        if position.max_vote > 1:
            this_key = pos + "[]"
            form_position = form.get(this_key)
            if form_position is None:
                continue
            if len(form_position) > max_vote:
                messages.error(request, "You can only choose " +
                               str(max_vote) + " candidates for " + position.name)
                return redirect(reverse('index'))
            else:
                for form_candidate_id in form_position:
                    form_count += 1
                    try:
                        candidate = Candidate.objects.get(id=form_candidate_id, position=position)
                        vote = Votes()
                        vote.candidate = candidate
                        vote.voter = voter
                        vote.position = position
                        vote.save()

                    except Exception as e:
                        messages.error(
                            request, "Please, browse the system properly " + str(e))
                        return redirect(reverse('index'))
        else:
            this_key = pos
            form_position = form.get(this_key)
            if form_position is None:
                continue
            # Max Vote == 1
            form_count += 1
            try:
                form_position = form_position[0]
                candidate = Candidate.objects.get(position=position, id=form_position)
                vote = Votes()
                vote.candidate = candidate
                vote.voter = voter
                vote.position = position
                vote.save()
            except Exception as e:
                messages.error(
                    request, "Please, browse the system properly " + str(e))
                return redirect(reverse('index'))

    # Count total number of records inserted
    # Check it viz-a-viz form_count
    inserted_votes = Votes.objects.filter(voter=voter)
    if (inserted_votes.count() != form_count):
        # Delete
        inserted_votes.delete()
        messages.error(request, "Please try voting again!")
        return redirect(reverse('index'))
    else:
        # Update Voter profile to voted
        voter.voted = True
        voter.save()
        messages.success(request, "Thanks for voting")
        return redirect(reverse('index'))

When a poll is create, and a candidate is added to that poll, a voter can vote any candidate, my problem now is if a voter already voted, that voter cannot vote again even when another poll is created, what i want is a voter can still vote in another poll regardless of voting on a poll already