diff --git a/lib/activitypub/federate.ts b/lib/activitypub/federate.ts
index 43e670a..23f78aa 100644
--- a/lib/activitypub/federate.ts
+++ b/lib/activitypub/federate.ts
@@ -72,7 +72,10 @@ async function cacheActor(actorObject: ActorObject) {
 	await getConnection().manager.save(actor);
 }
 
-async function fetchActor(url: string): Promise<ActorObject | null> {
+async function fetchActor(url?: string): Promise<ActorObject | null> {
+	if (!url) {
+		return Promise.resolve(null);
+	}
 	return new Promise((resolve, reject) => {
 		request({
 			url,