public class Program
 {
     private const int I2cDeviceBusID = 1;
     private const int AdcControllerChannel = 0;

     public static void Main()
     {
         DateTime sasTokenValidUntilUtc = DateTime.UtcNow;

         Debug.WriteLine($"{DateTime.UtcNow:HH:mm:ss} devMobile.IoT.RAK.Wisblock.AzureIoTHub.RAK11200.PowerBaseline starting");

         Configuration.SetPinFunction(Gpio.IO04, DeviceFunction.I2C1_DATA);
         Configuration.SetPinFunction(Gpio.IO05, DeviceFunction.I2C1_CLOCK);

         if (!WifiNetworkHelper.ConnectDhcp(Config.Ssid, Config.Password, requiresDateTime: true))
         {
             if (NetworkHelper.HelperException != null)
             {
                 Debug.WriteLine($"{DateTime.UtcNow:HH:mm:ss} WifiNetworkHelper.ConnectDhcp failed {NetworkHelper.HelperException}");
             }

             Thread.Sleep(Timeout.Infinite);
         }

         string uri = $"{Config.AzureIoTHubHostName}.azure-devices.net/devices/{Config.DeviceID}";

         // not setting Authorization here as it will change as SAS Token refreshed
         HttpClient httpClient = new HttpClient
         {
             SslProtocols = System.Net.Security.SslProtocols.Tls12,
             HttpsAuthentCert = new X509Certificate(Config.DigiCertBaltimoreCyberTrustRoot),
             BaseAddress = new Uri($"https://{uri}/messages/events?api-version=2020-03-13"),
         };

         I2cConnectionSettings settings = new(I2cDeviceBusID, Shtc3.DefaultI2cAddress);
         I2cDevice device = I2cDevice.Create(settings);
         Shtc3 shtc3 = new(device);

         AdcController adcController = new AdcController();
         AdcChannel batteryChargeAdcChannel = adcController.OpenChannel(AdcControllerChannel);

         string sasToken = "";

         while (true)
         {
             DateTime standardisedUtcNow = DateTime.UtcNow;

             Debug.WriteLine($"{DateTime.UtcNow:HH:mm:ss} Azure IoT Hub device {Config.DeviceID} telemetry update start");

             if (sasTokenValidUntilUtc <= standardisedUtcNow)
             {
                 sasTokenValidUntilUtc = standardisedUtcNow.Add(Config.SasTokenRenewEvery);

                 sasToken = SasTokenGenerate(uri, Config.Key, sasTokenValidUntilUtc);

                 Debug.WriteLine($" Renewing SAS token for {Config.SasTokenRenewFor} valid until {sasTokenValidUntilUtc:HH:mm:ss dd-MM-yy}");
             }

             if (!shtc3.TryGetTemperatureAndHumidity(out var temperature, out var relativeHumidity))
             {
                 Debug.WriteLine($" Temperature and Humidity read failed");

                 continue;
             }

             double batteryCharge = batteryChargeAdcChannel.ReadRatio() * 100.0;

             Debug.WriteLine($" Temperature {temperature.DegreesCelsius:F1}°C Humidity {relativeHumidity.Value:F0}% BatteryCharge {batteryCharge:F1}%");

             string payload = $"{{\"RelativeHumidity\":{relativeHumidity.Value:F0},\"Temperature\":{temperature.DegreesCelsius.ToString("F1")}, \"BatteryCharge\":{batteryCharge:F1}}}";

             try
             {
                 using (HttpContent content = new StringContent(payload))
                 {
                     content.Headers.Add("Authorization", sasToken);

                     using (HttpResponseMessage response = httpClient.Post("", content))
                     {
                         Console.WriteLine($"{DateTime.UtcNow:HH:mm:ss} Response code:{response.StatusCode}");

                         response.EnsureSuccessStatusCode();
                     }
                 }
             }
             catch (Exception ex)
             {
                 Debug.WriteLine($"{DateTime.UtcNow:HH:mm:ss} Azure IoT Hub POST failed:{ex.Message} {ex?.InnerException?.Message}");
             }

             Debug.WriteLine($"{DateTime.UtcNow:HH:mm:ss} Azure IoT Hub telemetry update done");

             Thread.Sleep(Config.TelemetryUploadInterval);
         }
     }
...
}