WD Enumerated Dropdown Value Getting cleared in Adobe PDF After submit

We have created a PDF adobe form using the webdynpro Abap in which we are using the Enumarated Drop Down list with the no select value. The Values are populating in the dropdown correctly and we are able to select the particular value from the dropdown.But when we submit the adobe form with the submit button to send it as an attachement in the workflow then the selected value of the dropdown gets cleared in the attachment. Is there any way to avoid that.

I have searched the forum for the same, but couldnt find appropriate solution. Please help.