Sample code

using System;

using System.Net.Http;

using System.Net.Http.Headers;

namespace EMA2Test

{

    public class AuthenticationData

    {

        public string Username { get; set; }

        public string Password { get; set; }

    }

    public class AuthenticationResponse

    {

        public string AccessToken { get; set; }

        public string RefreshToken { get; set; }

    }

    public class CompanyUserDetailsResponse

    {

        public string Id { get; set; }

        public string Name { get; set; }

        public int Type { get; set; }

    }

    public class UserDetailsReponse

    {

        public string Id { get; set; }

        public string FirstName { get; set; }

        public string LastName { get; set; }

        public string Email { get; set; }

        public string Description { get; set; }

        public string PhoneNumber { get; set; }

        public bool TwoFactorEnabled { get; set; }

        public int Status { get; set; }

        public CompanyUserDetailsResponse Company { get; set; }

    }

    public class UsageReportRequest

    {

        public DateTime From { get; set; }

        public DateTime To { get; set; }

        public int Skip { get; set; }

        public int Take { get; set; }

    }

    public class UsageReportProductResponse

    {

        public string ProductCode { get; set; }

        public string Name { get; set; }

        public int LicenseType { get; set; }

        public long SeatDays { get; set; }

    }

    public class UsageReportCompanyResponse

    {

        public UsageReportProductResponse[] Products { get; set; }

        public string CompanyId { get; set; }

        public string CompanyName { get; set; }

        public long TotalUsage { get; set; }

    }

    public class UsageReportResponse

    {

        public UsageReportCompanyResponse[] Companies { get; set; }

    }

    internal static class Program

    {

        private static HttpClient client = new HttpClient();

        private static string BaseURL = "https://mspapi.eset.com/";

        static void Main(string[] args)

        {

            client.BaseAddress = new Uri(BaseURL);

            client.DefaultRequestHeaders.Accept.Clear();

            client.DefaultRequestHeaders.Accept.Add(

                new MediaTypeWithQualityHeaderValue("application/json"));

            AuthenticationResponse authenticationResponse = Login();

            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", authenticationResponse.AccessToken);

            UserDetailsReponse userDetails = GetUserDetails();

            Console.WriteLine("User {0} is known under ID: {1}", userDetails.FirstName, userDetails.Id);

            Console.ReadLine();

            UsageReportResponse usageReport = GetUsageReport();

            client.Dispose();

        }

        static AuthenticationResponse Login()

        {

            var auth = new AuthenticationData { Username = "*****", Password = "*****" };

            HttpResponseMessage response = client.PostAsJsonAsync("/api/Token/Get", auth).Result;  

            if (response.IsSuccessStatusCode)

            {

                return response.Content.ReadAsAsync<AuthenticationResponse>().Result; 

            }

            else

            {

                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);

            }

            return null;

        }

        static UserDetailsReponse GetUserDetails()

        {

            var response = client.GetAsync("/api/User/Current").Result;

            if (response.IsSuccessStatusCode)

            {

                return response.Content.ReadAsAsync<UserDetailsReponse>().Result;

            }

            else

            {

                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);

            }

            return null;

        }

        static UsageReportResponse GetUsageReport()

        {

            var usagereportRequest = new UsageReportRequest { From = new DateTime(2019, 1, 1), To = new DateTime(2019, 1, 18), Skip = 0, Take = 100 };

            var response = client.PostAsJsonAsync("/api/UsageReport/AllCompanies/products", usagereportRequest).Result;

            if(response.IsSuccessStatusCode)

            {

                return response.Content.ReadAsAsync<UsageReportResponse>().Result;

            }

            else

            {

                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);

            }

            return null;

        }

    }

}