diff --git a/hunter/src/scheduler.rs b/hunter/src/scheduler.rs
index 1577631..680f6de 100644
--- a/hunter/src/scheduler.rs
+++ b/hunter/src/scheduler.rs
@@ -1,4 +1,4 @@
-use std::collections::{HashMap, BTreeMap};
+use std::collections::{HashMap, BTreeMap, hash_map};
 use std::sync::Arc;
 use std::time::Duration;
 use cave::feed::{Mention, Account};
@@ -86,13 +86,20 @@ impl Scheduler {
         let now = Instant::now();
         let host = introduce_host.host;
 
-        if let std::collections::hash_map::Entry::Vacant(entry) = self.instances.entry(host.clone()) {
-            entry.insert(Instance {
-                last_fetch: None,
-                error: false,
-                known_user: introduce_host.known_user,
-            });
-            self.queue.insert(now, host);
+        match self.instances.entry(host.clone()) {
+            hash_map::Entry::Vacant(entry) => {
+                entry.insert(Instance {
+                    last_fetch: None,
+                    error: false,
+                    known_user: introduce_host.known_user,
+                });
+                self.queue.insert(now, host);
+            }
+            hash_map::Entry::Occupied(ref mut entry) => {
+                if let Some(known_user) = &introduce_host.known_user {
+                    entry.get_mut().known_user = Some(known_user.clone());
+                }
+            }
         }
 
         true