Use A records + TXT instead of CNAME (CNAME cannot be combined with TXT)

domains/404.json

@@ -3,7 +3,7 @@
     "username": "audtjddld"
   },
   "records": {
-    "CNAME": "audtjddld.github.io",
+    "A": ["185.199.108.153", "185.199.109.153", "185.199.110.153", "185.199.111.153"],
     "TXT": ["_github-pages-challenge-audtjddld.404.is-a.dev=56294933a979f0aed3b984ebf5f686"]
   }
 }