diff --git a/src/plugin-sdk/allow-from.ts b/src/plugin-sdk/allow-from.ts
index a80360b610c..c41426d8b2e 100644
--- a/src/plugin-sdk/allow-from.ts
+++ b/src/plugin-sdk/allow-from.ts
@@ -71,7 +71,7 @@ export function isNormalizedSenderAllowed(params: {
     return true;
   }
   const sender = normalizeOptionalLowercaseString(String(params.senderId));
-  return normalizedAllow.includes(sender);
+  return sender ? normalizedAllow.includes(sender) : false;
 }
 
 type ParsedChatAllowTarget =