diff --git a/src/app/features/lobby/Lobby.tsx b/src/app/features/lobby/Lobby.tsx
index 069e925e..45610ff3 100644
--- a/src/app/features/lobby/Lobby.tsx
+++ b/src/app/features/lobby/Lobby.tsx
@@ -220,14 +220,12 @@ export function Lobby() {
       () =>
         hierarchy
           .flatMap((i) => {
-            const childRooms = Array.isArray(i.rooms)
-              ? i.rooms.map((r) => mx.getRoom(r.roomId))
-              : [];
+            const childRooms = Array.isArray(i.rooms) ? i.rooms.map((r) => getRoom(r.roomId)) : [];
 
-            return [mx.getRoom(i.space.roomId), ...childRooms];
+            return [getRoom(i.space.roomId), ...childRooms];
           })
           .filter((r) => !!r) as Room[],
-      [mx, hierarchy]
+      [hierarchy, getRoom]
     )
   );
 
diff --git a/src/app/features/lobby/SpaceItem.tsx b/src/app/features/lobby/SpaceItem.tsx
index 72830de4..2f91870b 100644
--- a/src/app/features/lobby/SpaceItem.tsx
+++ b/src/app/features/lobby/SpaceItem.tsx
@@ -474,7 +474,7 @@ export const SpaceItemCard = as<'div', SpaceItemCardProps>(
               </>
             )}
           </Box>
-          {canEditChild && (
+          {space && canEditChild && (
             <Box shrink="No" alignItems="Inherit" gap="200">
               <AddRoomButton item={item} />
               {item.parentId === undefined && <AddSpaceButton item={item} />}