diff --git a/modules/caissedepargne/pages.py b/modules/caissedepargne/pages.py
index 604f9b1d33a7141fa505d65e5948dfce5d78b538..163a231c1ded2bf36048fdcd505cbed8324c3581 100644
--- a/modules/caissedepargne/pages.py
+++ b/modules/caissedepargne/pages.py
@@ -1663,7 +1663,7 @@ class SmsRequestStep(LoggedPage, JsonPage):
 
 class SmsRequest(LoggedPage, JsonPage):
     def validate_key(self):
-        return self.doc['step']['validationUnits'][0].keys()[0]
+        return list(self.doc['step']['validationUnits'][0].keys())[0]
 
     def validation_id(self, key):
         return self.doc['step']['validationUnits'][0][key][0]['id']