Django imagefield don't shows on template - django

Question

i've a model with an imageField and when i upload file works and in database adds file path to img field
but when i try call it in my template seem is always empity item.img instead other fields works well, to show it i use a listview model
def content_file_name(instance, filename):
ext = filename.split('.')[-1]
# filename = "%s_%s.%s" % (instance, instance.questid.id, ext)
return f"uploads/items/{instance.id}.{ext}"
class Item(models.Model):
type = models.IntegerField(choices=TYPE, blank=False, default=NO_CAT)
name = models.CharField(max_length=250 )
description = models.CharField(max_length=250, blank=True )
img = models.ImageField(upload_to=content_file_name, blank=True)
tags = models.ManyToManyField(Tag, through='Item_Tags')
author = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.DO_NOTHING)
active = models.BooleanField(default=False)
created = models.DateTimeField(default=timezone.now)
updated = models.DateTimeField(auto_now=True)
def __str__(self): #metodo righiesto
return self.name
my template
<div class="card-columns">
{% for item in page_obj %}
<div class="card">
{% if item.img %}
<img class="card-img-top" src="{{item.image.url}}" alt="Card image cap">
{% else %}
NO image
{% endif %}
<div class="card-body">
<h5 class="card-title">{{item.name}}</h5>
<p class="card-text">{{item.description}}</p>
<p class="card-text"><small class="text-muted"></small></p>
</div>
</div>
{% endfor %}
</div>