diff --git a/crates/chattyness-user-ui/src/api/websocket.rs b/crates/chattyness-user-ui/src/api/websocket.rs
index 2bb109c..108034b 100644
--- a/crates/chattyness-user-ui/src/api/websocket.rs
+++ b/crates/chattyness-user-ui/src/api/websocket.rs
@@ -385,7 +385,7 @@ async fn handle_socket(
     let _ = channel_state.tx.send(join_msg);
 
     let user_id = user.id;
-    let is_guest = user.is_guest();
+    let mut is_guest = user.is_guest();
     let tx = channel_state.tx.clone();
 
     // Acquire a second dedicated connection for the receive task
@@ -1379,7 +1379,9 @@ async fn handle_socket(
                                     // Fetch updated user info from database
                                     match users::get_user_by_id(&pool, user_id).await {
                                         Ok(Some(updated_user)) => {
-                                            let is_guest: bool = updated_user.is_guest();
+                                            // Update the is_guest flag - critical for allowing
+                                            // newly registered users to send whispers
+                                            is_guest = updated_user.is_guest();
                                             let display_name = updated_user.display_name.clone();
 
                                             tracing::info!(
@@ -1389,6 +1391,19 @@ async fn handle_socket(
                                                 is_guest
                                             );
 
+                                            // Update WebSocket state with the new display name
+                                            // This is critical for whispers and mod commands to find
+                                            // the user by their new name after registration
+                                            if let Some(conn) = ws_state.get_user(user_id) {
+                                                ws_state.register_user(
+                                                    user_id,
+                                                    conn.direct_tx.clone(),
+                                                    conn.realm_id,
+                                                    conn.channel_id,
+                                                    display_name.clone(),
+                                                );
+                                            }
+
                                             // Broadcast identity update to all channel members
                                             let _ = tx.send(ServerMessage::MemberIdentityUpdated {
                                                 user_id,