diff --git a/tavern/_plugins/mqtt/response.py b/tavern/_plugins/mqtt/response.py
index 71c29702..02bf55d1 100644
--- a/tavern/_plugins/mqtt/response.py
+++ b/tavern/_plugins/mqtt/response.py
@@ -181,11 +181,12 @@ def addwarning(w, *args, **kwargs):
 
             self._maybe_run_validate_functions(msg)
         else:
-            self._adderr(
-                "Expected '%s' on topic '%s' but no such message received",
-                expected_payload,
-                topic,
-            )
+            if not self.expected.get("unexpected"):
+                self._adderr(
+                    "Expected '%s' on topic '%s' but no such message received",
+                    expected_payload,
+                    topic,
+                )
 
         if self.errors:
             if warnings:
@@ -198,6 +199,9 @@ def addwarning(w, *args, **kwargs):
 
         saved = {}
 
+        if not msg:
+            return saved
+
         saved.update(self.maybe_get_save_values_from_save_block("json", msg.payload))
 
         saved.update(self.maybe_get_save_values_from_ext(msg, self.expected))