Django error: Invalid block tag: expected 'endblock'

In the development environment it works normally, already on the production server I get the following error:

Invalid block tag: 'ultimos_produtos', expected 'endblock'

Here is the snippet of code:

{% extends "base.html" %}
{% load shop_tags i18n %}

{% block meta_title %}{% trans "Home" %}{% endblock %}
{% block title %}{% trans "Home" %}{% endblock %}

{% block breadcrumb_menu %}
<li class="active">{% trans "Home" %}</li>
{% endblock %}

{% block main %}

<h3> Em destaque </h3>
{% ultimos_produtos "perfumes" "span2" 3 %}

{% endblock %}

I'm using Django 1.8.16, Mezzanine 4.0.1.

The only difference between environments is that the production environment uses python 2.7.6 and python 2.7.8

Does anyone know what might be happening?