[Solved] FirebaseStorage Error: Invalid HTTP method/URL pair in ASP.Net

this is the error           

Response: {        "error": {        "code": 400,        "message": "Invalid HTTP method/URL pair."}}        }    

this is my code 

private async void bok_Click(object sender, EventArgs e)    
{        
    FileStream stream = File.Open(@"D:\a1.txt", FileMode.Open);
    var task = new FirebaseStorage("/newproject-be92d.appspot.com/")
        .Child("data")
        .Child("random")
        .Child("file.txt")
        .PutAsync(stream);
    task.Progress.ProgressChanged += (s, ee) => Console.WriteLine($"Progress: {ee.Percentage} %");        
    var downloadUrl = await task;        
}

Exception thrown: 'System.Reflection.TargetInvocationExc.dlleption' in mscorlib