diff --git a/src/Entity/StudiedLanguage.php b/src/Entity/StudiedLanguage.php
index 9d6596d9ce29de3ca38dae4b006435af5cb64ecc..55fc182297c2585c9ed2afbf857a1356264f5714 100644
--- a/src/Entity/StudiedLanguage.php
+++ b/src/Entity/StudiedLanguage.php
@@ -49,7 +49,7 @@ class StudiedLanguage
 
     public function __toString()
     {
-        return LanguagesIso::getLabelFromCode($this->getLanguage()) . ' : ' . $this->getLevel();
+        return LanguagesIso::getLabel($this->getLanguage()) . ' : ' . $this->getLevel();
     }
 
     /**
diff --git a/src/Manager/LanguagesManager.php b/src/Manager/LanguagesManager.php
index 1a3c1a1674911f847e3524e7457aa1e6c47d8afa..a8e7a7272b1970c4fcaf920b85b1ab7578680a82 100644
--- a/src/Manager/LanguagesManager.php
+++ b/src/Manager/LanguagesManager.php
@@ -18,6 +18,6 @@ class LanguagesManager
 {
     public function getLabel($code, $labelLanguage = 'fr')
     {
-        return LanguagesIso::getLabel($code);
+        return $code ? LanguagesIso::getLabel($code) : null;
     }
 }
diff --git a/templates/bundles/NelmioApiDocBundle/SwaggerUi/index.html.twig b/templates/bundles/NelmioApiDocBundle/SwaggerUi/index.html.twig
new file mode 100644
index 0000000000000000000000000000000000000000..5b78cf5462b5ebd12846ddf9142ff1b9c8b21b35
--- /dev/null
+++ b/templates/bundles/NelmioApiDocBundle/SwaggerUi/index.html.twig
@@ -0,0 +1,25 @@
+{#
+    To avoid a "reached nested level" error an exclamation mark `!` has to be added
+    See https://symfony.com/blog/new-in-symfony-3-4-improved-the-overriding-of-templates
+#}
+{% extends '@!NelmioApiDoc/SwaggerUi/index.html.twig' %}
+
+
+{% block stylesheets %}
+    {{ parent() }}
+    <style>
+        body {
+            margin-top: 0;
+        }
+    </style>
+{% endblock stylesheets %}
+
+    {% block header_block %}
+{#        <header>#}
+{#            {% block header %}#}
+{#                <a id="logo" href="https://github.com/nelmio/NelmioApiDocBundle">#}
+{#                    <img src="{{ nelmioAsset(assets_mode, 'logo.png') }}" alt="NelmioApiDocBundle">#}
+{#                </a>#}
+{#            {% endblock header %}#}
+{#        </header>#}
+    {% endblock header_block %}
\ No newline at end of file