private async void btnLogin_Click(object sender, EventArgs e) { panel3.Visible = false; List <string> lstInput = new List <string> { txtUsername.Text, txtPassword.Text }; if (Helper.ValidateTextFields(lstInput)) { LogInService _service = new LogInService(); var user = await _service.GetUserLoggedIn(txtUsername.Text, txtPassword.Text); if (user != null) { MessageBox.Show("Logged in."); } else { txtPassword.Text = ""; lblError.Text = "Invalid Username or Password"; panel3.Visible = true; } } else { lblError.Text = "Username and password are required"; panel3.Visible = true; } }