diff --git a/Program.cs b/Program.cs
index 3d90108..29bab0f 100644
--- a/Program.cs
+++ b/Program.cs
@@ -58,7 +58,7 @@ class Program
         {
             using (IDbConnection db = new NpgsqlConnection(connectionString))
             {
-                string query = "INSERT INTO users (chat_id, user_id, user_name) VALUES (@ChatId, @UserId, @UserName) ON CONFLICT (user_id) DO NOTHING";
+                string query = "INSERT INTO users (chat_id, user_id, user_name) VALUES (@ChatId, @UserId, @UserName) ON CONFLICT (chat_id, user_id) DO NOTHING";
 
                 var parameters = new
                 {