using Telagram api sendMessage and exportChatInviteLink return “chat not found” here is the code for invite:

 string token = ...
    string destId = "Existing Chat id I found from Bot raw in the destination telegram";
    string urlString = $"https://api.telegram.org/bot{token}/exportChatInviteLink?chat_id={destId}";
    var request = new HttpRequestMessage(System.Net.Http.HttpMethod.Get, urlString);
    HttpResponseMessage response = null;
    try
    {
        response = await _httpClient.SendAsync(request);
    }
    catch (Exception ex) { }
    TelegramModel result = null;
    //if (response.IsSuccessStatusCode)
    //{
    result = await response.Content.ReadFromJsonAsync<TelegramModel>();
    //}
    return result;// result;    

how to make this work?