[v2.0.0-develop-1][Xamarin] User SignUp

i was using parse sdk v2.0 in a Xamarin Forms Shared Project.
I am trying to register a new user using Source: https://github.com/parse-community/Parse-SDK-dotNET/#basic-demonstration

Steps to reproduce

Create a Xamarin Forms Shared Project. Install-Package parse -Version 2.0.0-develop-1
Copy Paste Code:

// Instantiate a ParseClient.
ParseClient client = new ParseClient(back4app_app_id,back4app_server_url, clientKey);

  var instal = client.Services.GetCurrentInstallation();
  // Create a user, save it, and authenticate with it.
  await client.SignUpAsync(username: "TestABC", password: "Test");

  // Get the authenticated user. This is can also be done with a variable that stores the ParseUser instance before the SignUp overload that accepts a ParseUser is called.
  var curUser=client.GetCurrentUser();

  // Deauthenticate the user.
  await client.LogOutAsync();

  // Authenticate the user.
  ParseUser user = client.LogInAsync(username: "Test", password: "Test").Result;

Actual Outcome

await client.SignUpAsync(username: "TestABC", password: "Test");
throws following exception:
System.ArgumentNullException: 'Value cannot be null.Parameter name: element'

Expected Outcome

After SignUpAsync() Function client.GetCurrentUser() should return current User

Environment

Server

• Parse Server version: 4.2.0
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): Back4APP

Client

• Parse .NET SDK version: -Version 2.0.0-develop-1
• Xamarin.Forms Project is .NET 2.1

Start with the basic demonstration linked in the issue and reproduce the SignUpAsync call in a Xamarin Forms project using the stated Parse .NET SDK version. Trace the ArgumentNullException and verify the fix by confirming signup completes and GetCurrentUser() returns the new user.