Setting System.Net.HttpWebRequest TransferEncoding to chunked always results in a exception

Question

I'm trying to understand whether I'm missing something or whether it's a limitation in HttpWebRequest setting the TransferEncoding value to chunked.

The below code works perfectly fine, as long as I set the SendChunked to true before I set the TransferEncoding value

        var httpWebRequest1 = (System.Net.HttpWebRequest)WebRequest.Create("https://SomeApiHost.com/api/v1");
        httpWebRequest1.SendChunked = true;
        httpWebRequest1.TransferEncoding = "gzip";

however if I attempt the following:

        var httpWebRequest2 = (System.Net.HttpWebRequest)WebRequest.Create("https://SomeApiHost.com/api/v1");
        httpWebRequest2.SendChunked = true;
        httpWebRequest2.TransferEncoding = "Chunked";

I always get this exception

Chunked encoding must be set via the SendChunked property. Parameter name: value

Using HttpClient works fine with the Chunked value, however I can't switch over to it as the RestSharp library uses HttpWebRequest

        var client1 = new System.Net.Http.HttpClient()
        client1.DefaultRequestHeaders.TryAddWithoutValidation("Transfer-Encoding", "chunked");
        client1.DefaultRequestHeaders.TransferEncodingChunked = true;

Does anyone know how to send the Chunked value in TransferEncoding with HttpWebReques?