private async void BtnLogin_Click(object sender, EventArgs e)
        {
            try
            {
                BaseAPIService.Username = txtUsername.Text;
                BaseAPIService.Password = txtPassword.Text;

                UserLoginRequest request = new UserLoginRequest()
                {
                    Username = txtUsername.Text,
                    Password = txtPassword.Text
                };

                Model.User loggedUser = await _apiService.Login(request);

                if (loggedUser != null)
                {
                    frmMain frm = new frmMain();
                    frm.Show();
                    this.Hide();
                }
                else
                {
                    MessageBox.Show("User not found", "ERROR", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
        async Task Login()
        {
            if (Username == null || Username == "" || Password == null || Password == "")
            {
                await Application.Current.MainPage.DisplayAlert("Error", "Username and password are required fields!", "OK");

                return;
            }

            UserLoginRequest user = new UserLoginRequest()
            {
                Username = Username,
                Password = Password
            };

            BaseAPIService.Username = user.Username;
            BaseAPIService.Password = user.Password;

            try
            {
                Model.User loggedUser = await _apiService.Login(user);

                if (loggedUser != null)
                {
                    BaseAPIService.Id            = loggedUser.Id;
                    BaseAPIService.Fullname      = loggedUser.FirstName + " " + loggedUser.LastName;
                    Application.Current.MainPage = new MainPage();
                }
                else
                {
                    await Application.Current.MainPage.DisplayAlert("Error", "Invalid username or password", "OK");

                    return;
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }