public async Task <IActionResult> OnPostAsync()
        {
            Conference = await _apiClient.GetConferenceAsync(Session.ConferenceID);

            ValidateSessionTime();

            if (!ModelState.IsValid)
            {
                await GetConferences();

                return(Page());
            }

            Message = "Session created successfully!";

            await _apiClient.AddSessionAsync(Session);

            return(RedirectToPage());
        }