Modal: [Bug] Modal does not show

I am using Blazor Serverside. Objective of the code is to display wait message

In button clicked i the following code

 Blazored.Modal.ModalReference modalRef = null;
 var myoptions = new Blazored.Modal.ModalOptions()
                {
                    // Class = "blazored-modal-movies",
                    HideCloseButton = false,
                    DisableBackgroundCancel = true,
                    Position = Blazored.Modal.ModalPosition.Center // "blazored-modal-bottomleft" // blazored-modal-center, blazored-modal-topleft, blazored-modal-topright, blazored-modal-bottomleft and blazored-modal-bottomright.
                };


                var myparameters = new Blazored.Modal.ModalParameters();
                  myparameters.Add("ModalMessage", "Please wiaiting...........");


                modalRef = modal.Show<mySite.Pages.ModalDialog>("Processing..", myparameters, myoptions);

In between this is my code that takes a while

modalRef.Close();

for me the Modal dialog does never shows up. the only other thing is that my button click is not async.