diff --git a/server/lib/room-channel/room-channel-class.ts b/server/lib/room-channel/room-channel-class.ts
index 44b8720b..ba0ec585 100644
--- a/server/lib/room-channel/room-channel-class.ts
+++ b/server/lib/room-channel/room-channel-class.ts
@@ -160,7 +160,6 @@ class RoomChannel {
         }
         c2r.set(roomJID, true)
         this.room2Channel.set(roomJID, channelId)
-        this.roomConfToUpdate.set(roomJID, true)
       }
     }
 
@@ -221,6 +220,11 @@ class RoomChannel {
     // This part must be done atomicly:
     this._readData(data)
 
+    // Now we must mark all rooms for conf update.
+    for (const roomJID of this.room2Channel.keys()) {
+      this.roomConfToUpdate.set(roomJID, true)
+    }
+
     await this.sync() // FIXME: or maybe scheduleSync ?
   }