Cant use models

Hi guys, I need some help. I'm using Phalcon and Volt. I use my model Users to save into database but when I try to make a simple for in Volt the compilers responds that variable users is not defined. Any advice?

{% block body %}
{{ "hello"|capitalize }}
ola
{% for user in users %}
 * Name : {{ user[name] }}
{% endfor %}
{% endblock %}