diff --git a/dudlebot.py b/dudlebot.py
index a530a7c..cdc0dce 100644
--- a/dudlebot.py
+++ b/dudlebot.py
@@ -82,7 +82,7 @@ class DudleBot:
                 responses.append(PlanResponse.UNKNOWN)
 
         user = update.message.from_user
-        name = user.username or ((user.first_name[0] + ". ") if user.first_name else '') + user.last_name
+        name = user.username or ((user.first_name[0] + ". ") if user.first_name else '') + (user.last_name or '')
 
         context.chat_data['plan'].entries[user.id] = PlanEntry(name=name, responses=responses)