diff --git a/src/Bundle/ChillMainBundle/Security/Resolver/CenterResolverManager.php b/src/Bundle/ChillMainBundle/Security/Resolver/CenterResolverManager.php
index 2dc947c8b..6f1b770bd 100644
--- a/src/Bundle/ChillMainBundle/Security/Resolver/CenterResolverManager.php
+++ b/src/Bundle/ChillMainBundle/Security/Resolver/CenterResolverManager.php
@@ -4,6 +4,8 @@ declare(strict_types=1);
 
 namespace Chill\MainBundle\Security\Resolver;
 
+use Chill\MainBundle\Entity\Center;
+
 final class CenterResolverManager implements CenterResolverManagerInterface
 {
     /**
@@ -20,7 +22,17 @@ final class CenterResolverManager implements CenterResolverManagerInterface
     {
         foreach($this->resolvers as $resolver) {
             if ($resolver->supports($entity, $options)) {
-                return (array) $resolver->resolveCenter($entity, $options);
+                $resolved = $resolver->resolveCenter($entity, $options);
+                if (null === $resolved) {
+                    return [];
+                } elseif ($resolved instanceof Center) {
+                    return [$resolved];
+                } elseif (\is_array($resolved)) {
+                    return $resolved;
+                }
+
+                throw new \UnexpectedValueException(sprintf("the return type of a %s should be an instance of %s, an array or null. Resolver is %s",
+                   CenterResolverInterface::class, Center::class, get_class($resolver)));
             }
         }
 
diff --git a/src/Bundle/ChillPersonBundle/Resources/views/Entity/person.html.twig b/src/Bundle/ChillPersonBundle/Resources/views/Entity/person.html.twig
index d0c5670aa..18c03bc92 100644
--- a/src/Bundle/ChillPersonBundle/Resources/views/Entity/person.html.twig
+++ b/src/Bundle/ChillPersonBundle/Resources/views/Entity/person.html.twig
@@ -149,10 +149,9 @@
                 {% endif %}
             </li>
             {% if options['addCenter'] and person|chill_resolve_center|length > 0 %}
-                {% set centers = person|chill_resolve_center %}
                 <li>
                     <i class="fa fa-li fa-long-arrow-right"></i>
-                    {% for c in centers %}
+                    {% for c in person|chill_resolve_center %}
                         {{  c.name|upper }}{% if not loop.last %}, {% endif %}
                     {% endfor %}
                 </li>