Use the right url reverse name for profile views.
{% extends "base.html" %}
{% load form_helpers %}
{% block title %}
{{task.title}}
{% endblock %}
{% block content %}
<h3>{{ task.title }}</h3>
{% if can_edit %}
<a href="{% url edit_task task.id %}">Edit task</a>
{% endif %}
{% if can_approve %}
<a href="{% url approve_task task.id %}">Approve task</a>
{% endif %}
{% if can_close %}
<a href="{% url close_task task.id %}">Close task</a>
{% endif %}
<hr />created by
<a href="{% url view_user_profile task.created_by.id %}">
{{ task.created_by.username }}
</a>
on {{task.creation_datetime|date:"D d M Y"}} at
{{task.creation_datetime|time:"H:i"}}
<br />
{% if reviewers %}
Reviewers:
{% for reviewer in reviewers %}
<a href="{% url view_user_profile reviewer.id %}">{{reviewer.username}}</a>
{% endfor %}
{% endif %}
{% if can_mod_reviewers %}
<a href="{% url addreviewer_task task.id %}">
Add a Reviewer to this task</a>
{% endif %}
<br />
<hr />
<b>Description:</b><br />
{{ task.desc|linebreaksbr }}
<br /><br /><hr />
{% if task.tags.count %}
Tags:
{% for tag in task.tags %}
{{tag}}
{% endfor %}
<hr />
{% endif %}
{% if selected_users %}
Users working on this task:
{% for user in selected_users %}
<a href="{% url view_user_profile user.id %}">{{user.username}}</a>
{% endfor %}
<br />
{% endif %}
{% if task_claimable %}
<a href="{% url claim_task task.id %}">View claims</a>
{% endif %}
<a href="{% url view_work task.id %}">View submitted work reports</a>
<hr />
{% if comments %}
comments:<br /><br />
{% for comment in comments %}
<a href="{% url view_user_profile comment.commented_by.id %}">
{{ comment.commented_by.username }}
</a>
on {{ comment.comment_datetime|date:"D d M Y"}} at
{{comment.comment_datetime|time:"H:i"}} wrote:
<br />
{{ comment.data|linebreaksbr }}<br />
{% endfor %}
{% endif %}
<hr />
{% if can_comment %}
Add comment:<br />
{% as_div_form form "Comment Form" csrf_token "Submit" %}
{% endif %}
{% endblock %}