--- a/mod_smacks/mod_smacks.lua	Sun Nov 07 14:30:24 2021 +0100
+++ b/mod_smacks/mod_smacks.lua	Sun Nov 07 14:41:43 2021 +0100
@@ -387,6 +387,8 @@
 		for i=1,#queue do
 			origin.log("debug", "Q item %d: %s", i, tostring(queue[i]));
 		end
+        origin:close{ condition = "undefined-condition"; text = "Client acknowledged more stanzas than sent by server"; };
+        return;
 	end
 
 	for i=1,math_min(handled_stanza_count,#queue) do