public static async Task<Users> searchUsers(string token, string search)
    {
        string query = String.Format("https://graph.microsoft.com/v1.0/users?$filter=startswith(displayname,'{0}') or startswith(surname,'{1}')", search, search);
        string users = null;
        httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
        HttpResponseMessage response = httpClient.GetAsync(query).Result;
        users = response.Content.ReadAsStringAsync().Result;
        Users usersJson = JsonConvert.DeserializeObject<Users>(users);
        return usersJson;
    }