diff --git a/cnames_active.js b/cnames_active.js
index 9295772d3a1..703d4ae0a78 100644
--- a/cnames_active.js
+++ b/cnames_active.js
@@ -54,6 +54,7 @@ var cnames_active = {
   "360": "360daili.github.io/360daili",
   "3d-go": "3d-go.netlify.app",
   "404": "licshee.github.io/404",
+  "520999": "5209999.github.io",
   "766": "766.github.io",
   "7anshuai": "7anshuai.github.io", // noCF? (don´t add this in a new PR)
   "8085sim": "ahmedazhar05.github.io/8085sim",