Invalid client type error while generating OAuth 2.0 authentication token for Google API in .NET MAUI Mobile Application

I am working on a .NET MAUI Mobile Application and trying to generate an OAuth 2.0 authentication token to call the Google Play Developer API. I have set up everything as follows:

1. Created a project on Google Cloud Console.
2. Enabled the Google Play Developer API.
3. Configured the OAuth consent screen with the external app type and added the "https://www.googleapis.com/auth/androidpublisher" as a scope.
4. Created an OAuth 2.0 Client ID with the application type set to Android, and added the package name along with the SHA-1 fingerprint.

In my .NET MAUI project, I have installed the following NuGet packages:

• Microsoft.Identity.Client
• System.Net.Http.Json

I implemented the OAuth flow for device code authentication. However, when I try to acquire an authentication token, I encounter the following error:

Error requesting device code: { "error": "invalid_client", "error_description": "Invalid client type." } Failed to acquire access token.

I implemented the OAuth flow for device code authentication as below:

public class GoogleAuthService
{
    private static readonly HttpClient _httpClient = new HttpClient();

    // Set your Client ID
    private const string ClientId = "Your_Google_Client_ID";

    // Set Google OAuth endpoints
    private const string DeviceCodeEndpoint = "https://oauth2.googleapis.com/device/code";
    private const string TokenEndpoint = "https://oauth2.googleapis.com/token";

    // Scopes needed for the Google Play Developer API
    private const string Scope = "https://www.googleapis.com/auth/androidpublisher";

    public async Task<string> GetAccessTokenAsync()
    {
        // Step 1: Request the device code
        var deviceCodeResponse = await RequestDeviceCodeAsync();

        if (deviceCodeResponse != null)
        {
            var deviceCode = deviceCodeResponse["device_code"].ToString();
            var userCode = deviceCodeResponse["user_code"].ToString();
            var verificationUrl = deviceCodeResponse["verification_url"].ToString();
            var expiresIn = deviceCodeResponse["expires_in"].ToString();
            var interval = int.Parse(deviceCodeResponse["interval"].ToString());

            // Instruct the user to visit the URL and input the user code
            Console.WriteLine($"Please visit {verificationUrl} and enter the code: {userCode}");

            // Step 2: Poll for the token using the device code
            return await PollForAccessTokenAsync(deviceCode, interval);
        }

        return null;
    }

    private async Task<JObject> RequestDeviceCodeAsync()
    {
        var parameters = new FormUrlEncodedContent(new[]
        {
            new KeyValuePair<string, string>("client_id", ClientId),
            new KeyValuePair<string, string>("scope", Scope)
        });

        var response = await _httpClient.PostAsync(DeviceCodeEndpoint, parameters);
        var responseBody = await response.Content.ReadAsStringAsync();

        if (response.IsSuccessStatusCode)
        {
            return JObject.Parse(responseBody);  // Return the device code response
        }

        Console.WriteLine($"Error requesting device code: {responseBody}");
        return null;
    }

    private async Task<string> PollForAccessTokenAsync(string deviceCode, int interval)
    {
        while (true)
        {
            await Task.Delay(interval * 1000);  // Wait for the polling interval

            var parameters = new FormUrlEncodedContent(new[]
            {
                new KeyValuePair<string, string>("client_id", ClientId),
                new KeyValuePair<string, string>("device_code", deviceCode),
                new KeyValuePair<string, string>("grant_type", "urn:ietf:params:oauth:grant-type:device_code")
            });

            var response = await _httpClient.PostAsync(TokenEndpoint, parameters);
            var responseBody = await response.Content.ReadAsStringAsync();

            if (response.IsSuccessStatusCode)
            {
                var tokenResponse = JObject.Parse(responseBody);
                var accessToken = tokenResponse["access_token"].ToString();
                Console.WriteLine($"Access Token: {accessToken}");
                return accessToken;  // Return the access token
            }
            else if (response.StatusCode == System.Net.HttpStatusCode.BadRequest)
            {
                var error = JObject.Parse(responseBody)["error"].ToString();
                if (error == "authorization_pending")
                {
                    Console.WriteLine("Authorization pending, waiting...");
                    continue;  // Keep polling
                }
                else
                {
                    Console.WriteLine($"Error: {error}");
                    return null;
                }
            }
        }
    }
}

To generate the access token from the below function, I call the GoogleAuthService();

public async void LoginButtonClicked(Object sender, EventArgs e)
{
    string accessToken = await _googleAuthService.GetAccessTokenAsync();

    if (!string.IsNullOrEmpty(accessToken))
    {
        // Use the access token to make API calls to Google Play Developer API
        Console.WriteLine($"Access Token: {accessToken}");
    }
    else
    {
        // Handle failure
        Console.WriteLine("Failed to acquire access token.");
    }
}

On AndroidManifest.xml file:

<activity android:name="MainActivity"
  android:exported="true">
    <intent-filter>
        <action android:name="android.intent.action.VIEW" />
        <category android:name="android.intent.category.DEFAULT" />
        <category android:name="android.intent.category.BROWSABLE" />
        <data android:scheme="com.googleusercontent.apps.OAuth 2.0 client ID" />
        <data android:host="oauth2redirect" />
    </intent-filter>
</activity>

What could be causing this "invalid_client" error? Is there something I'm missing in configuring the authentication token using OAuth 2.0 for the .NET MAUI Mobile Application to call the Google Play Developer API?