diff --git a/recommender-sys/rec-book-firebase/functions/package-lock.json b/recommender-sys/rec-book-firebase/functions/package-lock.json
index 529e7ed..4e57a99 100644
--- a/recommender-sys/rec-book-firebase/functions/package-lock.json
+++ b/recommender-sys/rec-book-firebase/functions/package-lock.json
@@ -558,11 +558,6 @@
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-        "handlebars": "^4.1.2",
-        "object.assign": "^4.1.0",
-        "promise": "^8.0.2"
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+        "handlebars": "^4.7.7"
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+        "handlebars": {
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+          "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.7.7.tgz",
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@@ -1534,7 +1546,8 @@
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@@ -2317,14 +2330,6 @@
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diff --git a/recommender-sys/rec-book-firebase/functions/package.json b/recommender-sys/rec-book-firebase/functions/package.json
index fcc4957..a490dcc 100644
--- a/recommender-sys/rec-book-firebase/functions/package.json
+++ b/recommender-sys/rec-book-firebase/functions/package.json
@@ -17,7 +17,7 @@
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     "cookie-parser": "~1.4.4",
     "express": "~4.16.1",
-    "express-handlebars": "^3.0.0",
+    "express-handlebars": "^5.3.1",
     "handlebars": "^4.7.6"
   },
   "devDependencies": {