diff --git a/src/request.js b/src/request.js
index fe8de851c1..ce5e95d5bb 100644
--- a/src/request.js
+++ b/src/request.js
@@ -45,7 +45,8 @@ async function init() {
  *  - For whatever reason `undici` needs to be required so that lookup can be overwritten properly.
  */
 function lookup(hostname, options, callback) {
-	const { ok, lookup } = checkCache.get(hostname);
+	let { ok, lookup } = checkCache.get(hostname);
+	lookup = [...lookup];
 	if (!ok) {
 		throw new Error('lookup-failed');
 	}
@@ -166,6 +167,10 @@ async function check(url) {
 		});
 	}
 
+	if (addresses.size < 1) {
+		return { ok: false };
+	}
+
 	// Every IP address that the host resolves to should be a unicast address
 	const ok = Array.from(addresses).every(({ address: ip }) => {
 		const parsed = ipaddr.parse(ip);