diff --git a/lib/index.js b/lib/index.js
index 2bbe773..50ab681 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -265,7 +265,11 @@ function anonymizeReplyText(replyText, userName) {
 }
 
 function errorHandler(err, req, res, next) {
-  res.status(400).json({ message: err.message });
+  if (err.message === "App not found (404)") {
+    res.status(404).json({ error: "App not found", message: err.message });
+  } else {
+    res.status(400).json({ error: "Bad Request", message: err.message });
+  }
   next();
 }
 
diff --git a/package-lock.json b/package-lock.json
index 96cd930..987429a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -25,7 +25,7 @@
         "eslint-plugin-standard": "^5.0.0",
         "newman": "^6.1.0",
         "newman-reporter-htmlextra": "^1.23.0",
-        "npm-check-updates": "^16.14.12"
+        "npm-check-updates": "^16.14.14"
       }
     },
     "node_modules/@aashutoshrathi/word-wrap": {
@@ -6418,9 +6418,9 @@
       }
     },
     "node_modules/npm-check-updates": {
-      "version": "16.14.12",
-      "resolved": "https://registry.npmjs.org/npm-check-updates/-/npm-check-updates-16.14.12.tgz",
-      "integrity": "sha512-5FvqaDX8AqWWTDQFbBllgLwoRXTvzlqVIRSKl9Kg8bYZTfNwMnrp1Zlmb5e/ocf11UjPTc+ShBFjYQ7kg6FL0w==",
+      "version": "16.14.14",
+      "resolved": "https://registry.npmjs.org/npm-check-updates/-/npm-check-updates-16.14.14.tgz",
+      "integrity": "sha512-Y3ajS/Ep40jM489rLBdz9jehn/BMil5s9fA4PSr2ZJxxSmtLWCSmRqsI2IEZ9Nb3MTMu8a3s7kBs0l+JbjdkTA==",
       "dev": true,
       "dependencies": {
         "chalk": "^5.3.0",