Microsoft Graph error - how to extract http-status from API

ref. the query same subject of 17 June 2020 and relevant answer.

1. ServiceException apparently is changed and now 'StatusCode' should be replaced by 'ResponseStatusCode'
2. I tried to catch it in the procedure to upload large files:

        try
        {
            // Upload the file
            var uploadResult = await fileUploadTask.UploadAsync(progress);

            sb.AppendLine(uploadResult.UploadSucceeded
                ? $"Upload complete, item ID: {uploadResult.ItemResponse.Id}" 
                : "Upload failed");
        }
        catch (ODataError ex)
        {
            sb.AppendLine($"Error uploading: {ex.Error?.Message}");
        }
        catch(ServiceException ex)
        { 
            sb.AppendLine($"Service exception: {ex.Message}");
            sb.AppendLine($"StatusCode: {ex.ResponseStatusCode}");
            ex.
        }
        catch (HttpRequestException ex)
        {
            sb.AppendLine($"HttpException: {ex.Message}");
            sb.AppendLine($"HttpRequestError: {ex.HttpRequestError}");
            sb.AppendLine($"StatusCode: {ex.StatusCode}");
        }
        catch (Exception ex)
        {
            sb.AppendLine(ex.Message);
        }
        finally
        {
            result.Text = sb.ToString();
        }

Disconnecting the Internet during the upload, I expect should throw ServiceException - but it doesn't. HttpRequestException is thrown instead, but in this case: Message = “An error occurred while sending the request”, HttpRequestError = 0 (unknown), StatusCode = null

So I am stuck with the original query: hot to extract the HTTP status?