diff --git a/seed/challenges/01-front-end-development-certification/basic-javascript.json b/seed/challenges/01-front-end-development-certification/basic-javascript.json
index 2cb9c20b33..5791dc7e21 100644
--- a/seed/challenges/01-front-end-development-certification/basic-javascript.json
+++ b/seed/challenges/01-front-end-development-certification/basic-javascript.json
@@ -4559,7 +4559,7 @@
         "    }",
         "};",
         "// Keep a copy of the collection for tests",
-        "var collectionCopy = JSON.parse(stringify(collection));",
+        "var collectionCopy = JSON.parse(JSON.stringify(collection));",
         "",
         "// Only change code below this line",
         "function updateRecords(id, prop, value) {",