diff --git a/ircrobots/sasl.py b/ircrobots/sasl.py
index 584f61c..8f3e21c 100644
--- a/ircrobots/sasl.py
+++ b/ircrobots/sasl.py
@@ -152,6 +152,8 @@ class SASLContext(ServerContext):
                     return SASLResult.SUCCESS
                 elif line.command == "904":
                     match.pop(0)
+            else:
+                break
 
         return SASLResult.FAILURE