Adt door and window sensor

Why cant Inadd the Smartthings ADT door and window sensor. It is not showing up under Smartthings or Samsung or ADT. Please help.

Which hub do you have and country are you in?

Adt Samsubg ST… usa… Ive had no problems adding this sensors on the classic app.

Can you describe the problem more? Is the option to add it not in your app or is the hub not finding it?