Web API not able to create the pages in sharepoint tenant

Following code from WebAPI is not able to create a new web page in sharepoint site .... but same code works with console application. With latestes Pnp.framework 1.7 it stops executing at AddClientSidePage

`
public class ValuesController : ApiController
{
// GET api/values
public IEnumerable Get()
{
string url = "https://svtech09.sharepoint.com/sites/SVSite001";
var autheticationManager = new AuthenticationManager();
var page = "mypage.aspx";

        using (var ctx = autheticationManager.GetACSAppOnlyContext(url, "client-id", "secret-key"))
        {
            Web web = ctx.Web;
            ctx.Load(web.Lists);
            ctx.Load(web, w => w.SupportedUILanguageIds);
            ctx.Load(web);

            ctx.ExecuteQueryRetry();
            //Create the Page
            var page2 = ctx.Web.AddClientSidePage(page, true);

            // Not executing above statement ... no exception also....Browser page shows loading indicator in header .....


            page2.AddSection(CanvasSectionTemplate.ThreeColumn, 5);
            page2.AddSection(CanvasSectionTemplate.TwoColumn, 10);
            page2.Save();
        }
        return new string[] { "value1", "value2" };
    }

`

Start with the ValuesController example and trace the call to ExecuteQueryRetry followed by AddClientSidePage. Compare this Web API flow with the console application where the same code works, then verify that page2.Save() completes and the page with its requested sections is created without the browser remaining in a loading state.