How do I solve Bluetooth Service errors in inthehand library

I can't find the solution for errors in the BluetoothService class in .NET MAUI. I get 2 errors:

bluetoothService does not contain a definition for SerialPort
bluetoothDeviceInfo does not contain a definition for Device

I googled it and saw suggestions that newer versions handle this differently. I downgraded to several older versions, but the errors remain. Two using directives that are supposed to be there are greyed out, which seems wrong.

Here is my code:

using Android.Bluetooth;
using InTheHand.Net.Sockets;
using System.Collections.ObjectModel;
using InTheHand.Net.Bluetooth;
using InTheHand.Net;

namespace ESP32_water_level_sensor.Platforms.Android
{
    public class BluetoothService : IBluetoothService
    {
        private BluetoothClient _client;
        private BluetoothSocket _socket;
        private Stream _stream;


        public async Task<ObservableCollection<BluetoothDeviceInfo>> GetPairedDevicesAsync()
        {
            _client = new BluetoothClient();
            var devices = _client.PairedDevices;
            return new ObservableCollection<BluetoothDeviceInfo>(devices);
        }

        public async Task<bool> ConnectToDeviceAsync(BluetoothDeviceInfo device)
        {
            try
            {
                // Connect to the device using the serial port UUID
                var serviceUuid = BluetoothService.SerialPort;
                _socket = device.Device.CreateRfcommSocketToServiceRecord(serviceUuid.Guid);
                await _socket.ConnectAsync();
                _stream = _socket.InputStream;
                return _socket.IsConnected;
            }
            catch (Exception ex)
            {
                System.Diagnostics.Debug.WriteLine($"Connection failed: {ex.Message}");
                return false;
            }
        }

        public async Task<string> ReadDataAsync()
        {
            if (_stream == null)
                return null;

            var reader = new StreamReader(_stream);
            // This will block until a line is received
            var line = await reader.ReadLineAsync();
            return line;
        }

        public void Disconnect()
        {
            _stream?.Dispose();
            _socket?.Dispose();
            _client?.Dispose();
        }
    }
}